GLM 0.9.7.2

Fixes:

• Fixed GTC_round floorMultiple/ceilMultiple #412
• Fixed GTC_packing unpackUnorm3x10_1x2 #414
• Fixed GTC_matrix_inverse affineInverse #192
• Fixed ICC on Linux build errors #449
• Fixed ldexp and frexp compilation errors
• Fixed "Declaration shadows a field" warning #468
• Fixed 'GLM_COMPILER_VC2005 is not defined' warning #468
• Fixed various 'X is not defined' warnings #468
• Fixed missing unary + operator #435
• Fixed Cygwin build errors when using C++11 #405