Deploy Symfony application on Platform.sh.
Fix typo and add Github link.
Github => GitHub
Better match Symfony documentation standard.

Based on feedbacks from @xabbuh and @timglabisch.
Reference available services
Add some references.
Fix duplicated references.

This should make the Travis build pass.
Use alphabetical order.
Fix coding standards #2

Thanks @WouterJ and @stof
Coding standard for PHP block.
Update map.rst.inc
feature #4526 Deploy Symfony application on Platform.sh. (GuGuss)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #4526).

Discussion
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Deploy Symfony application on Platform.sh.

Commits
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105088a Update map.rst.inc
257e9a8 Coding standard for PHP block.
18ca974 Fix coding standards #2
29988aa Use alphabetical order.
75a1c56 Fix duplicated references.
8fb400e Add some references.
a8b6df8 Reference available services
62f76bf Better match Symfony documentation standard.
b70f413 Github => GitHub
c2a5675 Fix typo and add Github link.
b4383b5 Deploy Symfony application on Platform.sh.
replace "or" with ","
minor #4691 replace "or" with "," (timglabisch)

This PR was merged into the 2.3 branch.

Discussion
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replace "or" with ","

See https://github.com/symfony/symfony-docs/pull/4405#discussion_r22293277
Just spelling.

Commits
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a950888 replace "or" with ","
Update form_customization.rst

There are two code samples which are inconsistent which each other. I updated one of them.
minor #4689 Update form_customization.rst (rodrigorigotti)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #4689).

Discussion
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Update form_customization.rst

This replaces a PR by @rodrigorigotti: https://github.com/symfony/symfony-docs/pull/4688. Many thanks to him!

Original PR description:

> There are two code samples which are inconsistent which each other. I updated one of them.

Commits
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4cd2046 Update form_customization.rst
Completed the needed context to successfully test commands
bug #4582 Completed the needed context to successfully test commands with Helpers (peterrehm)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes #4582).

Discussion
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Completed the needed context to successfully test commands with Helpers

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all
| Fixed tickets | #4581

As mentioned in symfony/symfony#12798 the explanation about the initialization is not clear.
Therefore I have added the needed context and a reference to the related cookbook article.

Commits
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a94bd71 Completed the needed context to successfully test commands
Merge remote-tracking branch 'upstream/2.3' into cookbook-grammar-and-style-fixes
Style / grammar fixes for the deployment chapter