Check for rst2man on posix doc rendering code path

To help for distros that rename the command (ubuntu).
Updated documentation

- Added custom layout with logo and navigation links
- Corrected command sorting
- Updated description
- Normalized case / naming
Update test to reflect latest doc changes
Merge branch 'brendandixon-update-docs' into develop

Closes #277.

* brendandixon-update-docs:
  Update test to reflect latest doc changes
  Updated documentation
Fix failing integ tests from #277

Also updated the usage strings to be consistent with the
`<command> <subcommand>` changes.
Merge branch 'jamesls-rst2man-ubuntu-fix' into develop

Closes #279, fixes #216

* jamesls-rst2man-ubuntu-fix:
  Check for rst2man on posix doc rendering code path
Add group_name to arguments

Also unify the public attrs that were added in CLIArgs
but not added to the base class.  In general, all public
interfaces need to be defined in the base CLI class to
make it clear what subclasses need to implement.
Add extra test for boolean arg merging
Merge branch 'merge-bools' into develop

* merge-bools:
  Add extra test for boolean arg merging
  Add group_name to arguments
Add docstring

As per review feedback.