* setup.py can install the manual (and by extension do can debuild)
* setup.py has (inactive) code for generating the html from the source
but this will break if rtd theme is not available
* A few changes to doc strings to make the autodoc prettier
* Added help shortcut, by default F1 to open the local manual
* Added button to About tab to launch manual
* A couple of additional string to translate related to manual/help
* Small tweak to setup.py to seperate build and install, and always attempt
to install manual by default.
* Small fix for systems (i.e. my 12.04 LTS) that don't set LANGUAGE for
whatever reason. This breaks the manual lookup