UMVE: Fix for retina displays
Merge pull request #103 from andre-schulz/win32

util::fs win32 fixes + GetTickCount64
MATH: Moved math::algo::round to math::round in functions.h, removed ND Gaussian
UTIL: Added missing include
OGL: Fixed fullscreen quad
MATH: Sanitized MATH_RAD2DEG and MATH_DEG2RAD macros
MVE: Use util::fs::join_path
UTIL: Made comments Doxygen compatible
UMVE: Updated umve.pro, fixes #107
UMVE: Rename QFileSelector to FileSelector

Rename UMVE's QFileSelector because a class with the same name was introduced in Qt 5.2.
Merge pull request #108 from andre-schulz/master

UMVE: Rename QFileSelector to FileSelector