v0.17.0
Fix py2.6 compat issues
Trim trailing white space throughout the project
Fix for issue #262 (non-existing tkinter imports in older py27 versions)
Merge in pending v0.16.x changes
drop -dev suffix
Skip the test not if it is OSX, but if it is Py3.6+, which appears to be the origination of the behavior breakage
Update copyright notices to 2018; Re-add Py2.6 and Py3.3 support; Update credits