Added tests for BelongsTo::__construct
Added tests for BelongsTo::getData
Added tests for BelongsToMany::__construct
Added tests for BelongsToMany::getNew
Added tests for BelongsToMany::getCountSubquery
Added tests for BelongsToMany::setDataFromCollection
Added tests for BelongsToMany::saveAll
Added comments on base test classes
Added flag to reset the container or not, saving memory