Added TextBlock

- This block has only text
- No title, or surrounding paragraph, just content.

For use for arbitary text on a website
Made document manager configurable for block loader
Renamed to StringBlock
BlockLoader: move DocumentManager from constructor to own setter
Updated/added tests for using block with multiple document managers
Merge pull request #54 from fazy/block-loader-workspace

[WIP] Made document manager configurable for block loader
Fixed test
Merge pull request #51 from dantleech/text_block

Added TextBlock
Cache: add varnish version and purgeinstruction
Merge pull request #55 from rmsint/update-esi-cache

Cache: add varnish version and purgeinstruction
this is incompatible with sonata block 2.2.1. fix #56
add newline at end of file
changed Symfony dependency to allow all future versions of 2.x
Merge pull request #60 from shieldo/patch-1

changed Symfony dependency to allow all future versions of 2.x
implement BlockContext
BlockContext: ActionBlock + RssBlock
BlockContext: update tests
BlockContext: action block config - PHPCRBlockLoader
drop symfony 2.1 support + added changelog
BlockContext: implement in caching adapters + RssController