Pipe screenfetch stderr to /dev/null

When running as root (via `sudo su`, for instance), XDG_RUNTIME_DIR is
usually not set, which causes some warning messages to be printed prior
to screenfetch's output. I don't care about this, so I don't want to see
it.

src/.bashrc

@@ -246,7 +246,7 @@ function _bashrc_randomcolor {
 # prints a message of the day (time, shell info, system info, etc.)
 function _bashrc_motd {
 	if type screenfetch >/dev/null; then
-		screenfetch
+		screenfetch 2>/dev/null
 		return
 	fi