Merge pull request #594 from hedgedoc/fix/pr_template

updated PR Template

.github/pull_request_template.md

@@ -6,12 +6,12 @@ This PR fixes/adds/improves/...
 
 ### Steps
 
-<!-- please tick steps this PR performs (if something is not necessary, please tick anyway to indicate you considered it) -->
+<!-- Please tick all steps this PR performs (if something is not necessary, please remove it) -->
 
-- [ ] added implementation
-- [ ] added / updated tests
-- [ ] added / updated documentation
-- [ ] extended changelog
+- [ ] Added implementation
+- [ ] Added / updated tests
+- [ ] Added / updated documentation
+- [ ] I read the [contribution documentation](https://github.com/hedgedoc/hedgedoc/blob/master/CONTRIBUTING.md) and signed-off my commits to accept the DCO.
 
 ### Related Issue(s)
 <!-- e.g #123 -->