Frontend-GNOME-IRC: add context menus to treeview node too

The context menus for IrcPersonChatView were only added for when the
user right clicks on the chat area, but not when the user right-clicks
on the treeview child element. Now they are added to both, and with no
code duplication.
Merge pull request #167 from knocte/master
Build: bumped version to 0.11
Merge branch 'stable'
Merge branch 'stable'
git-contributors: don't count merge commits
Merge branch 'stable'
Merge branch 'stable'
Engine-IRC: added translator hint for "Queuing joins" msg string
Merge branch 'stable'
Engine: implemented ProtocolManagerBase.ToString()
Engine: also scan for protocol managers in smuxi-engine.dll
Engine: also check name when looking up protocols
Engine, Frontend-GNOME: removed UrlMessagePartModel.Protocol
Engine(-Tests): implemented SmartLinks with some basic patterns (closes: #498, #911, #923)
Engine-Tests: added benchmarks for smartlinks
Engine(-Test): removed MessageBuilder.AppendRichText()
Engine(-Tests): applied coding standards
Engine-Tests: added test-case for broken mailto link
Engine: refactored MessageBuilderSettings for cleaner API, fixed mailto: and Smuxi bug links