Updates to the Zoom Controls page : structure, clarification, V7 layout

include/zoom-controls.html

@@ -1,14 +1,23 @@
 
-<figure class="left">
+<figure class="right">
   <img src="/images/toolbar-zoom.png" alt="Editor toolbar's zoom">
   <figcaption>
     Editor toolbar's zoom
   </figcaption>
 </figure>
 
-<p>The zoom controls allow to navigate the session along both the time and track axes.</p>
+<p>
+	The zoom controls allow to navigate the session along both the time 
+	and track axes. The controls are dscribed from right to left :
+</p>
 
-<p>The drop down <kbd class="menu">Zoom Focus</kbd> menu allows to select a focus point for the zoom, i.e. the center of the zoom. The choices are:</p>
+<h2 id="zoom-along-time-axis">Along the time axis</h2>
+
+<p>
+	The drop down <em>Zoom Focus</em> (<kbd class="menu">Playhead</kbd> 
+	by default) menu allows to select a focus point for the zoom, i.e. 
+	the center of the zoom, to choose amongst:
+</p>
 
 <ul>
   <li><dfn>Left</dfn> of the screen</li>
@@ -19,22 +28,55 @@
   <li><dfn>Edit Point</dfn> as set in the <a href="@@edit-point-control">Edit point</a> control.</li>
 </ul>
 
-<p>The two leftmost zoom buttons (<kbd class="menu">&minus;</kbd> and <kbd class="menu">&plus;</kbd>) use this zoom focus to zoom out and in respectively.<p>
+<p>
+	The two zoom buttons (<kbd class="menu">&minus;</kbd> and <kbd 
+	class="menu">&plus;</kbd>) use this zoom focus to zoom out and in 
+	respectively.
+<p>
 
-<p>The <kbd class="menu">Zoom to session</kbd> button is a handy shortcut to zoom out or in until all the session (as defined by its <a href="@@working-with-markers">start/end markers</a>) fits horizontally.</p>
+<p>
+	The <kbd class="menu">[&nbsp;]</kbd> <em>Zoom to session</em> 
+	button is a handy shortcut to zoom out or in until all the session 
+	(as defined by its <a href="@@working-with-markers">start/end 
+	markers</a>) fits horizontally.
+</p>
 
-<p>Changing the <kbd class="menu">Number of visible tracks</kbd> dropdown menu
-allows to fit this number of tracks vertically in the screen.<p>
+<h2 id="zoom-along-track-axis">Along the tracks axis</h2>
 
-<p class="note">There <em>is</em> a minimal track height to keep it visible, so
-according to you screen vertical size, some high number can have no effect.</p>
+<p>
+	Two buttons <kbd class="menu">Shrink tracks</kbd> and 
+	<kbd class="menu">Expand tracks</kbd> reduce or expand the vertical 
+	size of the selected tracks. If no track is selected, all the 
+	tracks will be shrunk or expanded each time the button is pushed.
+</p>
 
-<p>Inside this menu are two handy choices:</p>
+<p>
+	Last, the dropdown menu (<kbd class="menu">*</kbd> by default) 
+	allows changing the number of visible tracks to fit vertically on 
+	screen.
+<p>
+
+<p class="note">
+	There <em>is</em> a minimal track height to keep it visible, so 
+	according to the vertical screen size, some high number can have no 
+	effect.
+</p>
+
+<p>
+	Besides numbers that correspond to the number of tracks to show, 
+	there are two special choices:
+</p>
 
 <ul>
-  <li><dfn>Selected tracks</dfn> that focus on the selected tracks. If the selected tracks are not contiguous, the unselected tracks inbetween will be hidden, see the <a href="@@the-tracks-and-busses-list">Track and Bus list</a>.</li>
-  <li><dfn>All</dfn> that fits all the tracks of the sessions vertically (provided there's enough screen estate).</li>
+  <li>
+	<dfn>Selection</dfn> that focus on the selected tracks. If 
+	  the selected tracks are not contiguous, the unselected tracks 
+	  inbetween will be hidden, see the <a 
+	  href="@@the-tracks-and-busses-list">Track and Bus list</a>.
+  </li>
+  <li>
+	  <dfn>All</dfn> that fits all the tracks of the sessions 
+	  vertically (provided there's enough screen estate).
+  </li>
 </ul>
 
-<p>The rightmost buttons <kbd class="menu">Shrink tracks</kbd> and <kbd class="menu">Expand tracks</kbd> reduce or expand the vertical size of the selected tracks. If no track is selected, all the tracks will be shrunk or expanded each time the button is pushed.
-