Py 3 fixes

[joshmoore]

Collection of fixes found while working with scc under python 3.

• [x] fix scc version strings ("b'0.12.1')")
• [x] pip install --user under virtualenv leads to failure (build 11)
  • see:
  • see: https://stackoverflow.com/questions/33412974/how-to-uninstall-a-package-installed-with-pip-install-user
• [x] exception.message DNE (build 12)

See also:

• https://github.com/ome/build-infra/pull/20 (build 13)

[joshmoore]

Propose to release as 0.12.2.