SPEC shifted to ref runs

[Michael Hope]

We now do a SPEC ref run when benchmarking.  I've updated the
linaro-toolchain-benchmarks scripts to handle the changes and spawned
some historical builds to do comparisons.  All earlier builds have
been archived to prevent confusion.

The human readable summary is now also included in the results.  See:
 http://ex.seabright.co.nz/benchmarks/gcc-linaro-4.6-2012.02/logs/armv7l-natty-cbuild268-tcpanda06-cortexa9r1/spec2000-o3-neon-run.txt

for an example.

Half an hour to build, 26 hours to run.  Not too bad.

-- Michael