Revert "Version move to 2.0.0a1"

This reverts commit 4cd7d3062037dab13c99f0dd9b44f08fbd894ffa.
Merge branch 'pr/47' into release-1.8
Bump to 1.8.1 to release some outstanding changes.
Python 3.4 tested
Merge branch 'release-1.8'