Fixing Issue #2337: Commit dialog: recent commit messages list isn't updated aft…

Fixing Issue #2337 (closed): Commit dialog: recent commit messages list isn't updated after commits in other dialog windows

This could be pretty annoying issue as people would find loosing their commit message history or not displaying the correct commit message history quite a serious issue. The fix I have implemented is to always reload the current commit history before displaying or inserting a new one. Reloading the history from the registry multiple times should be a tiny performance hit.