Enable formatting toolbars in Pidgin

Originally created by @sajolida on #7356 (Redmine)

Currently in Tails the status of an OTR discussion is logged in the chat and depicted in the OTR menu. I think it would be good to activate by default the Formatting Toolbars (Options → Show Formatting Toolbars) to also have to OTr button in there that explicit with words (Private/Not private) the status of an OTR conversation.

That would also make our pidgin interface consistent with the OTR documentation we are linking to at Security-in-a-Box.

As a bonus, I sometimes get some formatting enabled without willing to (things get underlined, etc.). Having this toolbar enabled by default would make the formatting options more visible.

This toolbar has been deactivated back in 2009 with commit c4a2668. I’m not sure we thought about the implications on the OTR button while doing this, and we have nothing about that either in Redmine and no mailing list archives going that far.

Feature Branch: feature/7356-visible-otr-status

Parent Task: #7348 (closed)