Create an org-wide PR template?

[kdmccormick]

As a result of openedx/open-edx-proposals#171, an initial pull request template was introduced to edx-platform.

Acceptance criteria:

• Determine whether the PR template is being used consistently.
• If so: Make it the default template across all Open edX repositories (using .github meta-repository?). Repositories should be able to opt-out of the template or use a custom one if they so choose.
• If not: Choose to either (1) use linting to enforce the template, (2) find out why the template isn't being used and improve it, or (3) delete the template.

[sarina]

The way templated issues work is that a child repo will inherit all the issue templates from .github unless they define any of their own templates in a .github/ISSUE_TEMPLATE/ directory. I would think PR templates would be similarly overridable.

Anyway I very much support this effort! I get a bit frustrated sometimes when I encounter PRs without enough detail.

[kdmccormick]

Somewhat related: openedx/edx-cookiecutters#243