Snippet support

- Introducing support for writing snippets
Merge branch 'hotfix/smart-content-sort' into develop
Merge branch 'hotfix/smart-content-sort' into develop
Merge branch 'hotfix/block-event' into develop
resetted composer dependencies
Merge branch 'master' of git://github.com/sulu-cmf/SuluContentBundle into develop
Merge branch 'hotfix/seo' into develop

Conflicts:
	composer.json
fixed codestyle and interfaces
added type parameter
Improved test speed
Do not use PHP to execute shell scripts
Merge branch 'enhancement/faster_tests' into develop
Merge branch 'hotfix/empty-block' into develop

Conflicts:
	composer.json
Merge branch 'develop' of git://github.com/sulu-cmf/SuluContentBundle into feature/snippets
Merge branch 'master' of git://github.com/sulu-cmf/SuluContentBundle into develop

Conflicts:
	composer.json
fixed overlay open issue
Merge pull request #263 from sulu-cmf/bugfix/overlay-memory-leaks

fixed overlay open issue
Updated tests to be more efficient
Updated travis
Isolated nodecontroller test