Added in library required

This will make this script more portable, if I want to
run it on its own for some reason
Realised I need the key to access the RMA data

I'm still using Brian's RMA data (because it's
quicker to get to an interesting point) so I need
the key again.

I really should merge this into the
array_probeset_analysis part because this is an
advance on that really...
Altered process by which probes are selected

Used bit score and thresholds from Li et al Jetset paper to select
high scoring matches and ignored probes that detect more than one
of these genes (best I can do without the genome).

Problem putting gene name to the probes used because you have to go
through the contig names and end up with fewer probes to look at
as a result so I think I'm going to do this from scratch
Removed the forward/reverse duplication