Update fsharp to 3.1.1.28 to fix building without the 2.0 profile.
Update fsharp to 3.1.1.28 to fix building without the 2.0 profile.

mono/bockbuild,BansheeMediaPlayer/bockbuild,BansheeMediaPlayer/bockbuild,BansheeMediaPlayer/bockbuild,mono/bockbuild