Feature/no request context

[eacaps]

Added support for server rendering in ActionMailer contexts. Work was primarily done for #486 and this pull request was resubmitted to squash the commits.

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This change is

[coveralls]

Coverage increased (+0.04%) to 82.338% when pulling c1f5295 on eacaps:feature/no-request-context into 63436ab on shakacode:master.

[justin808]

2 minor issues:

1. Typo in the changelog.
2. the commit message could be just a few line, such as what is in the changelog entry.

Thanks again @eacaps! Great job!

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Reviewed 6 of 6 files at r1.
Review status: all files reviewed at latest revision, 1 unresolved discussion.

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CHANGELOG.md, line 8 [r1] (raw file):

## [Unreleased]

- React on Rails server rendering can now be used in contextes without request, mostly useful for usage in ActionMailer templates [#486](https://github.com/shakacode/react_on_rails/pull/486)

Typo contextes

React on Rails server rendering now supports contexts outside of browser rendering, such as ActionMailer templates [#486](https://github.com/shakacode/react_on_rails/pull/486)

I also like to put in author attribution! See a bit further below.

(ps., feel free to fill in in the others directly missing below)

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Comments from Reviewable

[justin808]

@eacaps I look forward to your update. If you can't get to it, please let me know.

[coveralls]

Coverage increased (+0.04%) to 82.338% when pulling 60afe39 on eacaps:feature/no-request-context into c77d3b6 on shakacode:master.

[justin808]

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Reviewed 1 of 1 files at r2.
Review status: all files reviewed at latest revision, 1 unresolved discussion, some commit checks failed.

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Comments from Reviewable

[justin808]

Big thanks @eacaps!