adding glm_vec2_center #116

Job	Run time
build_emsdk (Release)	58s
build_wasi_sdk (Release, 19)	28s
build_wasi_sdk (Release, 20)	30s
build_emsdk (Release, -msimd128)	1m 12s
build_wasi_sdk (Release, -msimd128, 19)	30s
build_emsdk (Release, -msse -msse2 -msimd128)	59s
build_wasi_sdk (Release, -msimd128, 20)	30s
build_emsdk (Release, -msse -msse2 -msse3 -msse4 -msimd128)	1m 16s
build_wasi_sdk (Debug, 19)	37s
build_emsdk (Debug)	59s
build_wasi_sdk (Debug, 20)	38s
build_emsdk (Debug, -msimd128)	1m 3s
build_wasi_sdk (Debug, -msimd128, 19)	33s
build_emsdk (Debug, -msse -msse2 -msimd128)	1m 9s
build_wasi_sdk (Debug, -msimd128, 20)	37s
build_emsdk (Debug, -msse -msse2 -msse3 -msse4 -msimd128)	1m 2s
build_wasi_sdk (RelWithDebInfo, 19)	31s
build_emsdk (RelWithDebInfo)	1m 0s
build_wasi_sdk (RelWithDebInfo, 20)	29s
build_emsdk (RelWithDebInfo, -msimd128)	1m 1s
build_wasi_sdk (RelWithDebInfo, -msimd128, 19)	38s
build_emsdk (RelWithDebInfo, -msse -msse2 -msimd128)	1m 7s
build_wasi_sdk (RelWithDebInfo, -msimd128, 20)	40s
build_emsdk (RelWithDebInfo, -msse -msse2 -msse3 -msse4 -msimd128)	1m 2s
build_wasi_sdk (MinSizeRel, 19)	32s
build_emsdk (MinSizeRel)	1m 0s
build_wasi_sdk (MinSizeRel, 20)	36s
build_emsdk (MinSizeRel, -msimd128)	57s
build_emsdk (MinSizeRel, -msse -msse2 -msimd128)	55s
build_emsdk (MinSizeRel, -msse -msse2 -msse3 -msse4 -msimd128)	58s
build_wasi_sdk (MinSizeRel, -msimd128, 19)	39s
build_wasi_sdk (MinSizeRel, -msimd128, 20)	41s
	25m 47s

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