add docs on how we want folks to submit PRs

[aaronlippold]

For example:

Development

Submitting a PR

1. A complete PR should include 7 core elements:
2. A signed PR ( aka git commit -a -s )
3. Code for the new functionality
4. Updates to the CLI
5. New unit tests for the functionality
6. Updates to the docs and examples in README.md and ./docs/*
7. (if needed) Example / Template files ( metadata.yml,example.yml, etc )
8. Scripts / Scaffolding code for the Example / Template files ( generate_map is an example )
9. Example Output of the new functionality if it produces an artifact

Overview of our PR process.

1. open an issue on the main inspec_tools website noting the issues your PR will address
2. fork the repo
3. checkout your fork
4. cd to the repo
5. git co -b
6. bundle install
7. hack as you will
8. test via rake
9. ensure unit tests still function and add unit tests for your new feature
10. add new docs to the README.md and to ./docs/examples
11. update the CLI as needed and add in usage example
12. (if needed) create and document any example or templates
13. (if needed) create any supporing scripts
14. (opt) gem build inspec_tools.gemspec
15. (opt) gem install inspec_tools
16. (opt) test via the installed gem
17. git commit -a -s
18. Open a PRs aginst the MITRE inspec_tools repo