Update composer.json

Bump dependency of doctrine common for symfony 2.1 users.
merged branch guilhermeblanco/patch-3 (PR #202)

This PR was submitted for the master branch but it was merged into the 2.1 branch instead (closes #202).

Commits
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3fa2c5c Update composer.json

Discussion
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Update composer.json

Bump dependency of doctrine common for symfony 2.1 users.
Fixed build error 'WARNING: unknown document: annotations/routing#activation'
merged branch WouterJ/fix_build_error (PR #212)

This PR was merged into the 2.1 branch.

Discussion
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Fixed build error 'WARNING: unknown document: annotations/routing#activation'

this should also get merged into 2.2 and master

Commits
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9c3bbb9 Fixed build error 'WARNING: unknown document: annotations/routing#activation'
Merge branch '2.1' into 2.2

* 2.1:
  Fixed build error 'WARNING: unknown document: annotations/routing#activation'
  Update composer.json

Conflicts:
	composer.json
Merge branch '2.2'

* 2.2:
  Fixed build error 'WARNING: unknown document: annotations/routing#activation'
  Update composer.json