Show Pomodoro Name in Menu Bar

Adds the name of the current Pomodoro to the menu bar. I've found this is really helpful for keeping on track, especially during those difficult "debug feature foo on Facebook" Pomodoros. Not sure if you are interested and happy to mod as desired but thought I'd send it you an initial pull to get the conversation started.

Likely could use an option in the application (at present it's wired to a unsurfaced option like show time)

Thanks,
Kav