Revert 268bbf2e and 99f2601a
Revert 268bbf2e and 99f2601a

As discussed in #1295: Reverting changes that were implemented in attempting to address issues encountered in CI testing, which were eventually fixed within TravisCI itself and hence these changes are not required.

MRtrix3/mrtrix3,MRtrix3/mrtrix3,MRtrix3/mrtrix3,MRtrix3/mrtrix3,MRtrix3/mrtrix3,MRtrix3/mrtrix3