Created attachment 530 [details]
blank-error.png

After pulling the master branch to get the latest changes, I got a blank error message when launching Hob (see attached blank-error.png). When you click the 'Close' button in the error, Hob closes. 

Shane explained this is due to Hob keeping old settings that might be invalid after the branch updates. It can be fixed by issuing 'rm .hob/ -rf' to clear any old settings. 

If this error is detected at launch, Hob should clear any old settings itself so that users don't need to see the error, issue the command themselves and then relaunch.

See the attached 'clearing up old settings message.png' and 'clearing up old settings message - annotated.png' for details of the design, which follow the Gnome HIG (http://developer.gnome.org/hig-book/3.0/windows-progress.html.en), which say: "If progress of a task makes a window temporarily unusable, do not present a modal dialog-like progress window in front of it. Instead, present progress somewhere in the original window, making all its other elements temporarily insensitive. This helps reduce visual clutter."

I am assuming that the process will not take too long, so I have not included a 'Cancel' option. If this assumption is incorrect, we will need to add a 'Cancel' button.