[OptionsResolver] Adjusted the OptionsResolver documentation to describe the 2.6 API
Added missing mailer class and use statements
Removed duplicate use statements
Merge pull request #1 from peterrehm/patch-9

Added mailer class and use statements
Updated OptionsResolver documentation: removed static methods
feature #4159 [WCM][OptionsResolver] Adjusted the OptionsResolver documentation to describe the 2.6 API (webmozart, peterrehm)

This PR was merged into the master branch.

Discussion
----------

[WCM][OptionsResolver] Adjusted the OptionsResolver documentation to describe the 2.6 API

| Q             | A
| ------------- | ---
| Doc fix?      | no
| New docs?     | yes (symfony/symfony#11716, symfony/symfony#12156)
| Applies to    | 2.6+
| Fixed tickets | -

Commits
-------

575c320 Updated OptionsResolver documentation: removed static methods
fab825d Merge pull request #1 from peterrehm/patch-9
f202fb8 Removed duplicate use statements
ae66893 Added missing mailer class and use statements
43ae1d8 [OptionsResolver] Adjusted the OptionsResolver documentation to describe the 2.6 API