implemented memoize
added phpdoc
refactored memoize
implemented call with arguments
added default life time parameter
added memoize to navigation twig extension
moved twig extensions
adapted config
added services
implemented memoized content twig extension
modified service config
fixed typo
implemented sitemap memoized extension
implemented snippet memoized extension
fixed testcase
fixed code style
fixed code style
Merge branch 'develop' of git://github.com/sulu-cmf/sulu into feature/twig-momoize
fixed changelog
Merge pull request #528 from sulu-cmf/feature/twig-momoize

Added memoize service and use it in twig extension