Add CLI commands to get version

[yani]

This PR adds the -version and -v commands to make the executable output the KFX version to stdout.

This is useful for third party tools like Unearth, launchers and others.

I also changed the VER_STRING variable in the make file to not have a trailing space when no package suffix is set.

Example:

$ keeperfx.exe -v
KeeperFX 1.0.0.0

Also works with Wine. Although Wine shows some extra stuff that should be fixed elsewhere.