document github issues

Author: bmarwell

.github/pull_request_template.md

@@ -1,14 +1,14 @@
 Following this checklist to help us incorporate your 
 contribution quickly and easily:
 
- - [ ] Make sure there is a [JIRA issue](https://issues.apache.org/jira/browse/MJLINK) filed 
-       for the change (usually before you start working on it).  Trivial changes like typos do not 
-       require a JIRA issue.  Your pull request should address just this issue, without 
+ - [ ] Make sure there is a [GitHub issue](https://github.com/apache/maven-jlink-plugin/issues) filed
+       for the change (usually before you start working on it).  Trivial changes like typos do not
+       require a GitHub issue.  Your pull request should address just this issue, without
        pulling in other changes.
  - [ ] Each commit in the pull request should have a meaningful subject line and body.
- - [ ] Format the pull request title like `[MJLINK-XXX] - Fixes bug in ApproximateQuantiles`,
-       where you replace `MJLINK-XXX` with the appropriate JIRA issue. Best practice
-       is to use the JIRA issue title in the pull request title and in the first line of the 
+ - [ ] Format the pull request title like `[#<num>] - Fixes bug in ApproximateQuantiles`,
+       where you replace `#<num>` with the appropriate GitHub issue. Best practice
+       is to use the GitHub issue title in the pull request title and in the first line of the
        commit message.
  - [ ] Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
  - [ ] Run `mvn clean verify` to make sure basic checks pass. A more thorough check will 

pom.xml

@@ -48,8 +48,8 @@
   </scm>
 
   <issueManagement>
-    <system>jira</system>
-    <url>https://issues.apache.org/jira/browse/MJLINK</url>
+    <system>GitHub</system>
+    <url>https://github.com/apache/maven-jlink-plugin/issues</url>
   </issueManagement>
   <ciManagement>
     <system>Jenkins</system>