Lots of work

1) moved clang integration down to the model level.
2) Added ability to scan projects for a file by path name.
3) Added ability to get the Clang.Cursor at caret location, this enables
more efficient intellisense.
4) Intellisense improvements for multiple overloads,
5) C++ support for intellisense (constructors, destructors and
overloads)
6) Error list now fixed, and navigating to the file and location
associated with error.
7) error list contains unique items only added to as new errors are
found.
8) each projectFile contains its own Translation unit.