[pitivi] help: update the Ruler section in mainwindow.page

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

commit f71ac26a055a836e002b91927898a3ecacf9e32d
Author: Tomas Karger <tomkarger gmail com>
Date:   Fri Jan 31 16:05:50 2014 +0100

    help: update the Ruler section in mainwindow.page

 help/C/mainwindow.page |    5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)
---
diff --git a/help/C/mainwindow.page b/help/C/mainwindow.page
index 993d277..20cde35 100644
--- a/help/C/mainwindow.page
+++ b/help/C/mainwindow.page
@@ -50,15 +50,14 @@
 
     <section>
      <title>Ruler</title>
-      <p>The ruler plays a crucial role in your interaction with the timeline. In addition to giving you 
time measurements (in seconds), it is the primary way of moving the playhead (and thus, your position in 
time).</p>
+      <p>The ruler plays a crucial role in your interaction with the timeline. First, it represents a time 
scale providing time measurements (in seconds) for overall orientation. Second, it constitutes the primary 
surface on which you can move the playhead (and thus, change your position in time). To move your position, 
click anywhere on the ruler. You can also <em>scrub</em> the timeline by clicking on the ruler and holding 
down the mouse button while moving. See the section on <link xref="movearoundtimeline">scrubbing</link> for 
more details.</p>
       <p>The current playhead position is indicated by a red vertical line:</p>
       <figure>
         <media type="image" src="figures/ruler.png" mime="image/png" style="right"></media>
       </figure>
       <note>
-       <p>When zoomed in, frames are visually represented on the ruler as alternating light and dark areas 
in the bottom part; those are based on the project framerate settings.</p>
+       <p>When zoomed in, frames are visually represented as alternating light and dark areas in the bottom 
part of the ruler. Hovering the mouse cursor over the ruler in this state will reveal an information tooltip 
with frame number. The amount of time the individual frames take up is based on the project framerate 
settings.</p>
       </note>
-      <p>To move your position in time, click anywhere on the ruler. You can also <em>scrub</em> the 
timeline by clicking on the ruler and holding down the mouse button while moving. See the section on <link 
xref="movearoundtimeline">scrubbing</link> for more details.</p>
     </section>
 
     <section>