language_in config parameter to closure filter.

Assetic supports setting the language_in command line flag of Google Closure Compiler, this feature is really needed in AsseticBundle too.
feature #313 language_in config parameter to closure filter. (dicorato)

This PR was merged into the 2.4-dev branch.

Discussion
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language_in config parameter to closure filter.

Assetic supports setting the language_in command line flag of Google Closure Compiler, this feature is needed in AsseticBundle too.

Commits
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e933a0f language_in config parameter to closure filter.