[TYPO3-mvc] Caching implemented

[Sebastian KurfŸürst]

Hi everybody,

after a nice brainstorming with Bastian, I implemented cache-clearing in 
Extbase (in revision 933). It's still a bit rough and definitely needs 
some benchmarking, but works in general.

The simple idea is that the storage backend will just clear the cache of 
the page the record is stored in, and taking the TSConfig clearCacheCmd 
into account.

This makes (here, at my installation) the blogexample work nicely.

Please test this implementation and don't hesitate to make improvement 
suggestions :-)

Greets,
Sebastian