* general
  - expand manpage with details and hairy issues (like nvidia bug #315920)

* nVidia backend:
  - Warn if interal display not connected; such is required for the workaround
    to bug #315920.
  - Cycling between different configurations (bug #315090)
  - Make tv-output work.
  - When switching between two external displays, go via the internal display as
    a workaround for bug #315920.

* complete XrandR backend

* investigate ati backend