Move local function 'getJsonOuput' to cli utils.

So it is available for other commands as well.
Added command 'stage-clean-smartdc'
Removed dead reference
Fix typo
Added docs for 'stage-clean-smartdc' command
Added reference to 'stage-clean-smartdc' command
Added man-page for 'sdc-clean-smartdc' command
Bump version to 0.8.1