When diffing with TSVN and there's only one path changed in a revision, use that path directly.
(Closes issue #357) : Direct diff, if only one file changed
Take the height of the filter checkbox into account when resizing the message control.
(Fixes issue #355) : Log message box too tall, last line gets Aero glass'd
Remember the state of the filter checkbox.
(Fixes issue #356) : The Show commits from ignored users checkbox does not stay checked when you minimize and maximize the app