Add D-Bus Method To Reload Theme

If you modify the theme, the only way to reload is to killall feedbackd since D-Bus has no way to stop services as far as I can tell. This seems like a bad idea to require killing the process. Thank you for your consideration, I understand if you believe this idea doesn't make sense in this project since the theme is stored in a directory meant to be read-only. This could be easily implemented as just exiting the process, since any calls to the D-Bus will automatically start it again.