Remove usage of deprecated function setFallbackLocale
Use new debug component
Remove unused imports and fix docblock for exceptions
Also update doc for translation changes
Handle locale_fallback
Test for TranslationServiceProvider
merged branch project-a/master (PR #791)

This PR was merged into the master branch.

Discussion
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Change deprecated functions and remove unused imports

I changed the deprecated translation function setFallbackLocale() and the debug Exception- and Error-Handler.
Therefore i added symfony/debug to composer.json.

I also removed unused imports and fixed some classnames in docblock comments.

Commits
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d214e2e Test for TranslationServiceProvider
67c7e3f Handle locale_fallback
380792b Also update doc for translation changes
60baead Remove unused imports and fix docblock for exceptions
69756f9 Use new debug component
92d4f0f Remove usage of deprecated function setFallbackLocale