fixed removing not existing documents in groups (fixes #28, 34)
removed debug
misc fixes in doc blocks and little formatting
misc fixes in doc blocks
misc fixes in doc blocks
Merge branch 'doc-block-fixes'

Conflicts:
	src/Mandango/DataLoader.php
	src/Mandango/Document/Document.php
	src/Mandango/Document/EmbeddedDocument.php
	src/Mandango/Group/PolymorphicReferenceGroup.php
	src/Mandango/Id/IdGeneratorContainer.php
	src/Mandango/Mandango.php
	src/Mandango/Query.php
	src/Mandango/Repository.php
	src/Mandango/Type/Container.php
	src/Mandango/UnitOfWork.php
	src/Mandango/UnitOfWorkInterface.php