Add DateTimeOffset and remove Sync methods settings in all specs

[vrdmr]

Adding DateTimeOffset settings and remove SyncMethods=node settings.

---

This checklist is used to make sure that common issues in a pull request are addressed. This will expedite the process of getting your pull request merged and avoid extra work on your part to fix issues discovered during the review process.

PR information

• The title of the PR is clear and informative.
• There are a small number of commits, each of which have an informative message. This means that previously merged commits do not appear in the history of the PR. For information on cleaning up the commits in your pull request, see this page.
• Except for special cases involving multiple contributors, the PR is started from a fork of the main repository, not a branch.
• If applicable, the PR references the bug/issue that it fixes.
• Swagger files are correctly named (e.g. the api-version in the path should match the api-version in the spec).

Quality of Swagger

• I have read the contribution guidelines.
• My spec meets the review criteria:
  • The spec conforms to the Swagger 2.0 specification.
  • The spec follows the guidelines described in the Swagger checklist document.
  • Validation tools were run on swagger spec(s) and have all been fixed in this PR.

[AutorestCI]

Automation for azure-libraries-for-java

Nothing to generate for azure-libraries-for-java

[AutorestCI]

Automation for azure-sdk-for-python

Encountered a Subprocess error: (azure-sdk-for-python)

Command: ['/usr/local/bin/autorest', '/tmp/tmptzya9at3/rest/specification/automation/resource-manager/readme.md', '--multiapi', '--python', '--python-mode=update', '--python-sdks-folder=/tmp/tmptzya9at3/sdk', '--use=@microsoft.azure/autorest.python@2.1.40', '--version=preview']
Finished with return code 1
and output:

AutoRest code generation utility [version: 2.0.4259; node: v7.10.1]
(C) 2018 Microsoft Corporation.
https://aka.ms/autorest

There is a new version of AutoRest available (2.0.4262).
 > You can install the newer version with with npm install -g autorest@latest

Failure:
Error: Unable to resolve package '@microsoft.azure/autorest-core@preview'.
Error: Unable to resolve package '@microsoft.azure/autorest-core@preview'.
    at fetch (/node_modules/@microsoft.azure/extension/dist/main.js:295:26)
    at /node_modules/npm/node_modules/call-limit/call-limit.js:22:12
    at _combinedTickCallback (internal/process/next_tick.js:73:7)
    at process._tickCallback (internal/process/next_tick.js:104:9)

[AutorestCI]

Automation for azure-sdk-for-node

The initial PR has been merged into your service PR:
Azure/azure-sdk-for-node#2653

[AutorestCI]

Automation for azure-sdk-for-go

Encountered a Subprocess error: (azure-sdk-for-go)

Command: ['/usr/local/bin/autorest', '/tmp/tmpyy6vxsgg/rest/specification/automation/resource-manager/readme.md', '--go', '--go-sdk-folder=/tmp/tmpyy6vxsgg/sdk', '--multiapi', '--use=@microsoft.azure/autorest.go@~2.1.95', '--use-onever', '--verbose']
Finished with return code 1
and output:

AutoRest code generation utility [version: 2.0.4259; node: v7.10.1]
(C) 2018 Microsoft Corporation.
https://aka.ms/autorest

There is a new version of AutoRest available (2.0.4262).
 > You can install the newer version with with npm install -g autorest@latest

   Loading AutoRest core      '/tmp/.autorest/@microsoft.azure_autorest-core@2.0.4259/node_modules/@microsoft.azure/autorest-core/dist' (2.0.4259)
   Loading AutoRest extension '@microsoft.azure/autorest.go' (~2.1.95->2.1.95)
   Loading AutoRest extension '@microsoft.azure/autorest.modeler' (2.3.38->2.3.38)
Processing batch task - {"tag":"package-2015-10"} .
Processing batch task - {"tag":"package-2017-05-preview"} .
Processing batch task - {"tag":"package-2018-01-preview"} .
FATAL: System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: startIndex
   at System.String.LastIndexOf(Char value, Int32 startIndex, Int32 count)
   at AutoRest.Go.Model.CodeModelGo.PackageVerDir() in C:\Users\autorest-ci\AppData\Local\Temp\2\PUBLISH2qmje\111_20180319T191725\autorest.go\src\Model\CodeModelGo.cs:line 64
   at AutoRest.Go.Model.CodeModelGo.get_DefaultUserAgent() in C:\Users\autorest-ci\AppData\Local\Temp\2\PUBLISH2qmje\111_20180319T191725\autorest.go\src\Model\CodeModelGo.cs:line 83
   at AutoRest.Go.Model.CodeModelGo.get_UserAgent() in C:\Users\autorest-ci\AppData\Local\Temp\2\PUBLISH2qmje\111_20180319T191725\autorest.go\src\Model\CodeModelGo.cs:line 31
   at AutoRest.Go.Templates.VersionTemplate.<ExecuteAsync>d__1.MoveNext() in C:\Users\autorest-ci\AppData\Local\Temp\2\PUBLISH2qmje\111_20180319T191725\autorest.go\src\obj\Razor\Templates\VersionTemplate.cshtml:line 28
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at AutoRest.Core.CodeGenerator.<Write>d__12.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at AutoRest.Go.CodeGeneratorGo.<Generate>d__6.MoveNext() in C:\Users\autorest-ci\AppData\Local\Temp\2\PUBLISH2qmje\111_20180319T191725\autorest.go\src\CodeGeneratorGo.cs:line 91
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at AutoRest.Go.Program.<ProcessInternal>d__3.MoveNext() in C:\Users\autorest-ci\AppData\Local\Temp\2\PUBLISH2qmje\111_20180319T191725\autorest.go\src\Program.cs:line 107
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NewPlugin.<Process>d__15.MoveNext()
FATAL: go/generate - FAILED
FATAL: Error: Plugin go reported failure.
Process() cancelled due to exception : Plugin go reported failure.
Failure during batch task - {"tag":"package-2018-01-preview"} -- Error: Plugin go reported failure..
  Error: Plugin go reported failure.

[anuchandy]

Sync-ed with Varad offline, service supports "DateTimeOffset" from the beginning, this PR is simply correcting swagger to reflect true service behavior.

The SDKs are already in preview so ok to break (DateTime -> DateTimeOffset). https://www.nuget.org/packages/Microsoft.Azure.Management.Automation/3.0.1-preview . This was generated from the tag (2018-preview) https://github.com/Azure/azure-rest-api-specs/blob/2aababee8801a3a43e2c74e9824ce7a632c11b04/specification/automation/resource-manager/readme.md#configuration