Allow the option to specify a fso build version during mod quicklaunch cmdline.

Options will be "-build build-id" and "-build-version version (optional)"

Also idea is to have 3 hardcoded version values for id "fso": NewerRelease, NewerRC, NewerNightly.

Looking at the code that is already written for mods in "Knossos.cs" this should be easy to add.