dictionary::get now supports retrieving stored handle by value if type is compatible

git-svn-id: http://svn.code.sf.net/p/angelscript/code@1997 404ce1b2-830e-0410-a2e2-b09542c77caf
Passing a non-lvalue expression to a &amp;out argument will now yield compiler error instead of warning


git-svn-id: http://svn.code.sf.net/p/angelscript/code@1998 404ce1b2-830e-0410-a2e2-b09542c77caf
Script classes can now inherit opConv and opImplConv from base class and add its own for other types

git-svn-id: http://svn.code.sf.net/p/angelscript/code@1999 404ce1b2-830e-0410-a2e2-b09542c77caf