cmake support

[Patrick Valsecchi]

Hi,

I was trying to build the latest from subsurface using cmake and it 
fails. Looks like the code now requires Qt5 and the CMakeLists.txt wants 
Qt4. There is a variable at the top that can be changed to make it use 
Qt5, but this is broken.

So, i was wondering...

1) Is cmake support dropped?
2) Is Qt4 support dropped?
3) Is anybody interested by a patch to make cmake work again and with Qt5?

I'm interested by cmake because the editor I want to try (CLion) uses 
cmake as project definition.

Thanks.