[meld] help: Add keyboard shortcut doc for folder expansion

[Kai Willadsen <kaiw src gnome org>]

commit e01b554246090722489d99cea95250584410d1f3
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Thu Jan 26 06:54:14 2017 +1000

    help: Add keyboard shortcut doc for folder expansion

 help/C/keyboard-shortcuts.page |   22 ++++++++++++++++++++++
 1 files changed, 22 insertions(+), 0 deletions(-)
---
diff --git a/help/C/keyboard-shortcuts.page b/help/C/keyboard-shortcuts.page
index be43613..7b2dc5e 100644
--- a/help/C/keyboard-shortcuts.page
+++ b/help/C/keyboard-shortcuts.page
@@ -102,6 +102,28 @@
 </table>
 
 <table frame="top bottom">
+  <title>Shortcuts for folder comparison</title>
+
+  <thead>
+    <tr>
+      <td><p>Shortcut</p></td><td><p>Description</p></td>
+    </tr>
+  </thead>
+
+  <tbody>
+    <tr>
+      <td><p><keyseq><key>+</key></keyseq></p></td>
+      <td><p>Expand the current folder.</p></td>
+    </tr>
+    <tr>
+      <td><p><keyseq><key>-</key></keyseq></p></td>
+      <td><p>Collapse the current folder.</p></td>
+    </tr>
+  </tbody>
+</table>
+
+
+<table frame="top bottom">
   <title>Shortcuts for view settings</title>
 
   <thead>