init cache manager & event listener
Merge branch 'develop' of git://github.com/sulu-cmf/sulu into feature/cache-expiration
refactored http cache manager
Merge branch 'develop' of git://github.com/sulu-cmf/sulu into feature/cache-expiration
Merge branch 'develop' of git://github.com/sulu-cmf/sulu into feature/cache-expiration
Merge branch 'develop' of git://github.com/sulu-cmf/sulu into feature/cache-expiration
Merge branch 'develop' of git://github.com/sulu-cmf/sulu into feature/cache-expiration
Merge branch 'develop' of git://github.com/sulu-cmf/sulu into feature/cache-expiration
updated symfony http-cache manager
added fos http-cache dependency
added symfony proxy client (cache manager)
added kernel.environment for http-cache event-listener
Merge branch 'develop' of git://github.com/sulu-cmf/sulu into feature/cache-expiration

Conflicts:
	composer.json
	src/Sulu/Component/Webspace/Manager/WebspaceManager.php
cleaned code
fixed tests
extended querybuilder to check for relational data and just receive certain fields
resolved one possible issue
Merge pull request #110 from sulu-cmf/feature/history-delete

[FEATURE] implemented delete / restore resource locator
Merge pull request #112 from sulu-cmf/feature/relational-fields

[FEATURE] RestApi: Receive certain rows of relational data
added filter options for responselist