Windows patch

This is a short patch to get it working in windows, it may be outdated,
and
GL exceptions will not work.

*Newer versions of GLEW "interferes" with OpenGL error exceptions,
- gl.h(211) the exception was commented

*Corrected the error "terminate called after throwing an instance of
'pangolin::UnknownTypeException' what():  Unknown type in generic
container
due the string comparasion"
- vars_internals.h(few places) every comparasion between char* and
string
was changed

* Added a missing term
-  timer.h (118) added the QuadPart member to f (the LARGEINTEGER
struct).
may need reworking for 32bits arch because this struct is
accessed by two independly members DWORD32 hi e low.