Update mono version for travis build to 3.10.0.
Update mono version for travis build to 3.10.0.

fscheck/FsCheck,sideeffffect/FsCheck,fsharp/FsCheck,paulyoung/FsCheck,forki/FsCheck,paulyoung/FsCheck,ploeh/FsCheck,ErikSchierboom/FsCheck,cloudRoutine/FsCheck,jhamm/FsCheck,cloudRoutine/FsCheck,forki/FsCheck,fscheck/FsCheck