2.2.0b1 release changes

Changes for release of version 2.1.0.

Updates specified in RELEASE.txt.

fix rest issue hat only shows up when running check with python3

Commits for roundup 2.0 release.

Removed tag 2.0.0beta0

More release doc updates.

Changes to prepare for 1.6.1 release.

add subhead for 1.6.0 release

Preparing 1.5.1 steps 7/16

7. python setup.py build_doc

  * fix include of basic.css for rendering permalink anchors
  * make anchors less obtrusive

Release preparation