Creating columns with array config

* Basic support
New DataSource: Doctrine2 Collections

Just a thin wrapper and move to PhpArray
PhpArray fix
BUGFIX: Export columns (PDF/Excel), Collection source
Merge pull request #42 from ZeinEddin/master

change the name of the attribute to reflect its content
BUGFIXES (see description)

* PHPExcel: Label translation
* GridId valid for cache
* TCPDF array type
Merge branch 'master' of https://github.com/ThaDafinser/ZfcDatagrid
UnitTests
more testing
Protototypes for testing
unfinished test
Update README.md