add a pull request template (and mention the CLA)

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,29 @@
+## Proposed changes
+
+Describe the big picture of your changes here to communicate to the maintainers why we should accept this pull request. If it fixes a bug or resolves a feature request, be sure to link to that issue.
+
+## Types of changes
+
+What types of changes does your code introduce to Appium?
+_Put an `x` in the boxes that apply_
+
+- [ ] Bugfix (non-breaking change which fixes an issue)
+- [ ] New feature (non-breaking change which adds functionality)
+- [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
+
+## Checklist
+
+_Put an `x` in the boxes that apply. You can also fill these out after creating the PR. If you're unsure about any of them, don't hesitate to ask. We're here to help! This is simply a reminder of what we are going to look for before merging your code._
+
+- [ ] I have read the [CONTRIBUTING](/CONTRIBUTING.md) doc
+- [ ] I have signed the [CLA](https://docs.google.com/forms/d/1lOfXRw_0VCk7gYzjj4WLetGu7yelDVo5LWh0z7pGftE/viewform)
+- [ ] Lint and unit tests pass locally with my changes
+- [ ] I have added tests that prove my fix is effective or that my feature works
+- [ ] I have added necessary documentation (if appropriate)
+- [ ] Any dependent changes have been merged and published in downstream modules
+
+## Further comments
+
+If this is a relatively large or complex change, kick off the discussion by explaining why you chose the solution you did and what alternatives you considered, etc...
+
+### Reviewers: @imurchie, @jlipps, ...

CONTRIBUTING.md

@@ -22,6 +22,10 @@ You will probably also want to have a look at this more in-depth [Developer's
 Overview](/docs/en/contributing-to-appium/developers-overview.md) of the Appium
 project, how Appium is architected, how to make changes to modules, and so on.
 
+Finally, before we accept your code, you will need to have signed our
+[Contributor License
+Agreement](https://docs.google.com/forms/d/1lOfXRw_0VCk7gYzjj4WLetGu7yelDVo5LWh0z7pGftE/viewform).
+
 ### Become an Appium Triager
 
 You can help us manage our issue tracker! All you need is enough familiarity