Clarify parameters conventions
fix form type.
Example of getting entity managers directly from the container

The documentation didn't provide examples of how to obtain the entity managers directly from the DI container.  This is useful when needing to inject the em into other services.

The ems are added to the container using the service id `doctrine.orm.%s_entity_manager`, where `%s` is the em's name.  This is done by `\Doctrine\Bundle\DoctrineBundle\DependencyInjection\DoctrineExtension::loadOrmEntityManager()` (see: https://github.com/doctrine/DoctrineBundle/blob/v1.2.0/DependencyInjection/DoctrineExtension.php#L347)
Contributions should be based off 2.3 or higher

Per the documentation (http://symfony.com/doc/current/contributing/documentation/overview.html#contributing), the base branch should be 2.3, not 2.2.
Update forms.rst

Hi there, 
I thought it would be nice to specify that you can set a label to false to disable it. I needed it for a project, couldn't find it in the doc, and had to search through a couple of stackoverflow posts to find the solution.
Update forms.rst

not sure what you meant about the wrapping, I applied a soft wrap after "to your input,".
Let me know how that looks
Update forms.rst
Fix typos
Wrap variables in {} for safer interpolation
Fix PSR error
Change interpolation to concatenation
Replace double quotes with single quotes
Fixing typo - thanks to @xabbuh
bug #3493 Type fix in remove.rst (weaverryan)

This PR was merged into the 2.3 branch.

Discussion
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Type fix in remove.rst

Hi guys!

Very minor typo fix... leaving the PR format off.

Thanks!

Commits
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efaad48 Fixing typo - thanks to @xabbuh
bug #3535 fix form type name. (yositani2002)

This PR was merged into the 2.3 branch.

Discussion
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fix form type name.

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

Commits
-------

ef4014d fix form type.
Add missing variable assignment

Line 41 made use of $crawler which wasn't defined.
bug #3537 Add missing variable assignment (colinodell)

This PR was submitted for the 2.2 branch but it was merged into the 2.3 branch instead (closes #3537).

Discussion
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Add missing variable assignment

Line 41 made use of $crawler which wasn't defined.

Commits
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8f41c15 Add missing variable assignment
Applied comment
minor #3528 Clarify service parameters usages (WouterJ)

This PR was merged into the 2.3 branch.

Discussion
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Clarify service parameters usages

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

On the IRC channel, there was some confusing about parameters. The dot
notation looked like parameters are one big namespaced tree, with each
group a different node.

This PR adds a caution, so people really know it's just a convention and
parameters are just key-value elements.

Commits
-------

aaddfcd Applied comment
05492b2 Clarify parameters conventions
Update generic_event.rst

The $event['data'] field was not set, thus it wouldn't be modified.

Also, the example already had a lowercase string. Uppercased 1 letter.