Added PR template

Author: sanderv32

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,29 @@
+## JENKINS-xxxxx/PR-xxxx - summarize pull request in one line
+
+Describe the big picture of your changes here to explain to the maintainers why we should accept this pull request. If it fixes a bug or resolves a feature request, include a link to the issue.
+
+## 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. This is simply a reminder of what we are going to look for before merging your code._
+
+- [ ] I have read the [CONTRIBUTING](https://github.com/jenkinsci/gogs-webhook-plugin/blob/master/CONTRIBUTING.md) doc
+- [ ] I have referenced the Jira/Github issue related to my changes in one or more commit messages
+- [ ] I have added tests that verify my changes
+- [ ] Unit tests pass locally with my changes
+- [ ] I have added documentation as necessary
+- [ ] No Javadoc warnings were introduced with my changes
+- [ ] No findbugs warnings were introduced with my changes
+- [ ] I have interactively tested my changes
+- [ ] Any dependent changes have been merged and published in upstream modules (like git-client-plugin)
+
+## Types of changes
+
+What types of changes does your code introduce? _Put an `x` in the boxes that apply_
+
+- [ ] Bug fix (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)
+
+## Further comments
+
+If this is a relatively large or complex change, start the discussion by explaining why you chose the solution you did and what alternatives you considered.