CMake

Merge viscosity branch of dlparkhurst/phreeqc3-1 into master #228

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Run time

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Job	Run time
🚧⚫ mingw32	17s
build (macos-latest)	1m 47s
build (ubuntu-latest)	2m 32s
build (windows-latest)	3m 44s
ctest (macos-latest)	1m 40s
ctest (ubuntu-latest)	2m 9s
ctest (windows-latest)	3m 13s
	15m 22s