Added README.txt to teach how to build with DQuest
DQSharedList - Changed the storage format , now it use QList < QSharedPointer<DQAbstractModel> > .
[Bug Fix] DQSharedList::clear() - It should not clear the binded metaInfo
Added a new function : dqmodel_cast() -  Returns the given abstract model cast to type T* if the model is of type T; otherwise returns 0. If model is 0 then it will also return 0.
DQ_MODEL : It will add a new function to DQModel - staticMetaInfo()

It is the static version of the metaInfo() function. You don't  need to create it for the derived class as long as you have  put the DQ_MODEL macro line in the class declaration.
dqmodel_cast() - Changed the argument type to make it similar to qobject_cast
DQList - Added append(DQList) , last() ,isEmpty()
DQWhere - Added example usage in the document
Extra test case to prove that multiple database connection works.
Merge commit 'bd3b651879d8b1a5446a7dd02ea15f3718bce1c6' into v0.3

Conflicts:
	tests/unittests/coretests.cpp
	tests/unittests/sqlitetests.cpp