linuxdvb: added missing LNBs and started on switch config
linuxdvb: added rotor object, though no implementation yet
misc: fix and simplify string procesing bug

previously this could create wildly inaccurate results for numbers with
a larger number of fractional digits. Combined with inaccuracy of representing
some numbers this could result in a roundtrip str -> double -> str ending
up with complete garbage.
linuxdvb: added rotor GOTOX/USALS implementation

This is taken from PR #238. I still don't have the movement duration stuff
done. And now I really need to think more about the config.
linuxdvb: fix some mistakes in switch properties
idnode prop: added floating point (double) property
linuxdvb: transition to diseqc send command in new code.
linxudvb: remove deprecated code

Some bits are still incomplete, but I can refer to copies from now on.