[Fuego] Creating single jobs without testplans

[Daniel Sangorrin]

Hi, 

I just made a small modification to the fuego-create-jobs script that
allows creating single jobs without the need of a testplan.
So it works like this:

# fuego-create-jobs -b raspi -c Benchmark.dbench

It selects the default spec for that test. If you want to provide a different spec you still need to provide
a testplan, but I can add another option (-s?) to do that.

This is just exploratory work, I know the implementation will have to be done from scratch
if we use jjb.

Cheers,
Daniel