[arch-dev-public] move hddtemp to extra

[Andreas Radke]

I'd like to move hddtemp from community to extra. It's of quiet high
usage according to http://www.archlinux.de/?page=PackageStatistics
and I'd like to use it for Xfce4-sensors-plugin to be able to show
hdd temps in the panel.

I have some small improvements for both packages done locally and they
work well together here showing two hard drives in the panel.

Any objections?

-Andy