Fix a Clang compilation error.

The issue here is that GLM_DEPRECATED, GL_ALIGN, etc is being left undefined with the Clang build.
Merge pull request #47 from mackron/Clang-Compile-Fix

Clang compilation error.
Clang detection for GLM_INLINE
Fixed conflict
Fixed conflict
Merge branch '0.9.5' of https://github.com/g-truc/glm into 0.9.5