Add Version information to RC template

[lahirumaramba]

• Add Version information to the Template
• Create new Version type
• Create new User type
• Note: Since Version and User types are output only, I did not implement equal() and hashcode() operations. Instead, unit tests are checking for each property in Version and User individually. I also removed the equality operations from Template, as well.
• Based on PR review feedback, implement equality in all public types (including Version and User) to keep consistency.

Related to: #446

[hiranya911]

It looks pretty solid. I only had some minor nits. But I do think we should support equals on the new classes. A developer might want to do something like the following:

if (!template1.getVersion().equals(template2.getVersion()) {
  // do something
}

It's also consistent with other classes in this package. WDYT?

[lahirumaramba]

I noticed that the update time is represented in FC3339 UTC "Zulu" format, accurate to nanoseconds. Added new code here to convert the timestamp to milliseconds properly.

DateTime does not handle nanoseconds so I had to drop them from the timestamp string before parsing. Otherwise SimpleDateFormat considers nanoseconds as milliseconds and add it back to the time making the parsed date/time incorrect.

Apparently, there are better ways to handle nanoseconds in Java8 (LocalDateTime and Instant) :)

[lahirumaramba]

Implemented equal() in all public types (including Version and User) to keep consistency

[hiranya911]

Thanks. This looks great. Just a few nits.

[hiranya911]

LGTM with a couple of suggestions.

[hiranya911]

indexOfPeriod can be possibly 0, in which case this will do substring(0, 0). I think following makes more sense to me:

String updateTime = versionResponse.getUpdateTime();
int indexOfPeriod = updateTime.indexOf('.');
if (indexOfPeriod != -1) {
  updateTime = updateTime.substring(0, indexOfPeriod);
}

[lahirumaramba]

I agree! This is better. Update the code. Thanks!

[hiranya911]

It's ok to define some of these as class level constants. For example templateNine can be a class-level constant, and templateTen can be initialized in the corresponding test case as a local var. Same goes for others.

[lahirumaramba]

I see what you mean now! Moved to class level constants. Thanks!