Fixed failing tests on OSX.
Merge pull request #208 from pelson/osx_tests

Fixed failing image comparison tests on OSX.
Merge remote branch 'cpelley/doc_index' into v0.6.x

* cpelley/doc_index:
  updated indexing
  updated toctree
  index file
  Moved master up to v0.7.x
Merge remote branch 'upstream/v0.6.x'

* upstream/v0.6.x:
  Fixed failing tests on OSX.