Add PR template

Author: norareidy

source/.github/pull_request_template.md

@@ -0,0 +1,14 @@
+# Pull Request Info
+
+[PR Reviewing Guidelines](https://github.com/mongodb/docs-rust/blob/master/REVIEWING.md)
+
+JIRA - <https://jira.mongodb.org/browse/DOCSP-NNNNN>
+Staging - <https://docs-mongodbcom-staging.corp.mongodb.com/drivers/docsworker-xlarge/NNNNN/>
+
+## Self-Review Checklist
+
+- [ ] Is this free of any warnings or errors in the RST?
+- [ ] Did you run a spell-check?
+- [ ] Did you run a grammar-check?
+- [ ] Are all the links working?
+- [ ] Are the [facets and meta keywords](https://wiki.corp.mongodb.com/display/DE/Docs+Taxonomy) accurate?