Implemented BelongsToMany::link
Renaming property and adding unit test for BelongsToMany::link()
Adding missing assert from previous commit
Some work towards implementing unlink()
Fixed bug with creating multicolum primary keys ins SQlite
Refectoring unlink and adding more tests
Documenting new methods
Fixed unit test
Completing unit tests fir unlink
Implementing BelongsToMany::replaceLinks
A bit of refactoring and completing the integration test
Adding more integration tests for replaceLinks
Allowing new target entities in replaceLinks()
Making replaceLinks transactional
Making link() transational too
Added unit test for missing primary key in replaceLinks
Adding a unit test for BelongsToMany::replaceLinks
Documenting new functions
Fixing coding standard errors
Fixing another CS error