Correct screen blanking

- Correct screen blanking, screensaver will no longer activate
  immediately upon login.
- Add test for Xresources file; will only attempt to load if the file
  exists.

Tested-on: zaphod <01 Apr 2014>
Fix duplicate call of xrdb

Removes second call of xrdb, only loading Xresources once per session

Tested-on: zaphod <01 Apr 2014>