Update PULL_REQUEST_TEMPLATE

Author: thornjad

.github/PULL_REQUEST_TEMPLATE

@@ -1,19 +1,23 @@
+**What changes did you make?**
+
+**Provide some example code that this change will affect, if applicable:**
+
+<!-- Paste the example code here: -->
+
+**Is there anything you'd like reviewers to focus on?**
+
 **Please ensure that your pull request fulfills these requirements:**
 - [ ] The pull request is being made against the `master` branch
 - [ ] Tests for the changes have been added (for bug fixes / features)
+- [ ] New features/options have been documented in:
+   - [ ] `http-server --help` text
+   - [ ] README.md
+   - [ ] doc/http-server.1
 
 **What is the purpose of this pull request? (bug fix, enhancement, new feature,...)**
 
 <!--
     Link to the issue this pull request fixes here, if applicable: "Fixes #xxx" or "Resolves #xxx"
+    
+    If your PR fixes multiple issues, list them individually like "Fixes #xx1, fixes #xx2, fixes #xx3". This is a quirk of how GitHub links issues.
 -->
-
-**What changes did you make?**
-
-**Provide some example code that this change will affect, if applicable:**
-
-<!-- Paste the example code here: -->
-
-**Is there anything you'd like reviewers to focus on?**
-
-**Please provide testing instructions, if applicable:**