Added GHC 7.8.3 to travis.
Added GHC 7.8.3 to travis.

Signed-off-by: Alex <60c6d277a8bd81de7fdde19201bf9c58a3df08f4@centromere.net>

thoughtpolice/hs-nacl,thoughtpolice/hs-nacl,thoughtpolice/hs-nacl,thoughtpolice/hs-nacl,thoughtpolice/hs-nacl