Linux/OSX support

[cpb8010]

VOSM supports Linux and OSX, but this project does not.
There are some leftover CMakefiles that were used previously, but they will have to be updated. All of the project dependencies are cross-platform, so those shouldn't be a problem.
The hard-coded paths in the solution file now should also be changed to environment variables, but this is only part of the problem.

This will probably be solved in part just by cleaning up the project and reducing the amount of build dependence on visual studio.