added a PR template to normalize those contributions from GitHub

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,12 @@
+Be sure to do all of the following to help us incorporate your contribution quickly and easily:
+
+ - [ ] Make sure the PR title is formatted like: `COMMONSRDF-XXX: title of pull request`
+   (replace `XXX` in the title with the actual Jira issue number; if there is no one,
+   please [create one](https://issues.apache.org/jira/browse/COMMONSRDF) before).
+ - [ ] Make sure tests pass via mvn clean verify (even better, enable Travis-CI on your
+   fork and ensure the whole test suite passes).
+ - [ ] If this contribution is large, please file an 
+   [Apache's Individual Contributor License Agreement](https://www.apache.org/licenses/icla.txt).
+
+---
+