add toolbar class for default toolbar layouting

Improved layout of discussion a bit
improved toolbar layout

PHPdocs and minor code cleanup

Cleanup of issues:
Close #138 - probably old javascript, toolbar works fine for me.
Close #144 - default behavior
Close #139 - there was no new update.., or do I miss understand the issue?
Close #100 - already fixed
Close #73 - PR for default hiding the discussion, duplicate of proposal issue 81
Close #60 - fixed, localization possible since commit 1171146
Close #59 - fixed with 1eedfbc , further improvements in issue 66
Close #42 fixed in include plugin
Close #62 lightbox is not installable, so issue not testable.