Update/fix googletest for VS2017 v15.5

[j-o]

googletest doesn't compile with the recent VS2017 update to v15.5, see google/googletest#1318.

[j-o]

googletest is fixed now, so an update would be in order. Did you change anything or just dump the entire source into cmake-init?

[scheibel]

That was our way to go. I hope everything works as expected with just replacing the contents in cmake-init/source/tests/googletest.

[scheibel]

Is this fixed with #78?

[j-o]

Yes