PARQUET-1579 Add Github PR template (apache#642)

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,26 @@
+Make sure you have checked _all_ steps below.
+
+### Jira
+
+- [ ] My PR addresses the following [Parquet Jira](https://issues.apache.org/jira/browse/PARQUET/) issues and references them in the PR title. For example, "PARQUET-1234: My Parquet PR"
+  - https://issues.apache.org/jira/browse/PARQUET-XXX
+  - In case you are adding a dependency, check if the license complies with the [ASF 3rd Party License Policy](https://www.apache.org/legal/resolved.html#category-x).
+
+### Tests
+
+- [ ] My PR adds the following unit tests __OR__ does not need testing for this extremely good reason:
+
+### Commits
+
+- [ ] My commits all reference Jira issues in their subject lines. In addition, my commits follow the guidelines from "[How to write a good git commit message](http://chris.beams.io/posts/git-commit/)":
+  1. Subject is separated from body by a blank line
+  1. Subject is limited to 50 characters (not including Jira issue reference)
+  1. Subject does not end with a period
+  1. Subject uses the imperative mood ("add", not "adding")
+  1. Body wraps at 72 characters
+  1. Body explains "what" and "why", not "how"
+
+### Documentation
+
+- [ ] In case of new functionality, my PR adds documentation that describes how to use it.
+  - All the public functions and the classes in the PR contain Javadoc that explain what it does

pom.xml

@@ -470,6 +470,7 @@
         <configuration>
           <consoleOutput>true</consoleOutput>
           <excludes>
+            <exclude>.github/PULL_REQUEST_TEMPLATE.md</exclude>
             <exclude>**/*.parquet</exclude>
             <exclude>**/*.avro</exclude>
             <exclude>**/*.json</exclude>