Re-organize README, split off contribution guide

This pull request is a starting point for improving the documentation prior to the upcoming brownbag.

Starting with the README and contribution guide, I'll be poring over the existing docs trying to come up with examples. I'm thinking the wiki here in git.doit will be helpful as well.

Adding a few others: @bjsousa @andrew-petro @levett @paul.erickson .

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Added 1 commit:

• 8cc037af - Correct link to wiki

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Status changed to merged

mentioned in commit bf106c8b