Automated conda packaging of openmm-dev [ready to merge]

This is a (potentially doomed) initial attempt at automated conda packaging of openmm-dev.
See here: http://docs.travis-ci.com/user/speeding-up-the-build/#Paralellizing-your-build-on-one-VM
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To give you an idea of what speedup are we talking about, I've tried running tests in parallel on travis-core and I was able to see a drop from about 26 minutes to about 19 minutes across 4 jobs.
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