[pitivi] help: add Timeline toolbar section to mainwindow.page

[Jean-François Fortin Tam <jfft src gnome org>]

commit b197e3d97bff29bacfa2ae88a9e0c3a8a49731b7
Author: Tomas Karger <tomkarger gmail com>
Date:   Wed Feb 5 17:18:10 2014 +0100

    help: add Timeline toolbar section to mainwindow.page

 help/C/mainwindow.page |   16 ++++++++++++++++
 1 files changed, 16 insertions(+), 0 deletions(-)
---
diff --git a/help/C/mainwindow.page b/help/C/mainwindow.page
index ec20207..9fb0066 100644
--- a/help/C/mainwindow.page
+++ b/help/C/mainwindow.page
@@ -79,6 +79,22 @@
     </section>
 
     <section>
+     <title>Timeline toolbar</title>
+      <p>The timeline toolbar is located at the right edge of the timeline. It contains basic actions for 
editing in timeline:</p>
+      <list>
+      <item><p>Split clip at playhead position</p></item>
+      <item><p>Delete selected</p></item>
+      <item><p>Group clips</p></item>
+      <item><p>Ungroup clips</p></item>
+      <item><p>Align clips based on their soundtracks</p></item>
+      <item><p>Toggle gapless mode</p></item>
+      </list>
+      <note>
+      <p>Note that most of the actions become available only once a clip is selected. When there is no 
subject for the action to be performed on, it remains shaded (indicating its unavailability).</p>
+      </note>
+    </section>
+
+    <section>
      <title>Playback toolbar</title>
       <p>This toolbar, located below the previewer, contains buttons controlling the playback of the 
timeline. Options provided by the toolbar are the following:</p>
       <list>