Add FireSim changes to the standard 2017 branch

[NathanTP]

@davidbiancolin added some handy scripts to Speckle2017 and made a few tweaks for FireSim. Should we try to merge these into the regular 2017 branch?

Major Changes:

• A bunch of train commands. I'm not sure what these do.
• A few tweaks to the default config (gcc version, CFLAGS)
• New intrate.sh intspeed.sh scripts that automate running the benchmarks and collect some metrics.
  • I'm in the process of adding a few more metrics to these.
  • They do include one firesim-specific performance counter collector. We could autodetect that if needed or generalize the
    metric collection to let users provide an additional measurement script.

Opinions?