Switched from QtHelp to using straight HTML files for help.

This is because AppImage (for linux) is readonly and QtHelp requires
write access. But, HTML files shouldn't.

help/temporalwindow.html

@@ -0,0 +1,43 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
+  "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
+
+<html xmlns="http://www.w3.org/1999/xhtml">
+  <head>
+    <meta http-equiv="X-UA-Compatible" content="IE=Edge" />
+    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
+    <title>Temporal Window</title>
+    <link rel="stylesheet" href="_static/nonav.css" type="text/css" />
+    <link rel="stylesheet" href="_static/pygments.css" type="text/css" /> 
+  </head><body>
+
+    <div class="document">
+      <div class="documentwrapper">
+          <div class="body" role="main">
+            
+  <div class="section" id="temporal-window">
+<h1>Temporal Window</h1>
+<p>.</p>
+<img alt="_images/TemporalWindow.png" src="_images/TemporalWindow.png" />
+</div>
+<div class="section" id="using-the-temporal-window">
+<h1>Using the Temporal Window</h1>
+<p>This window gives a dual graphical representation of CAN IDs over time. For each frame in the capture a circle is placed
+on the graph at a point given by the time when the frame came in on the X axis and the frame ID on the Y axis. That is, a frame with ID 0x300
+that comes in at 23.543 seconds would be plotted at the point 23.543, 0x300. The graph background is color coded for “density.” That brings up
+the question “What do you mean by density?” The answer is somewhat nebulous but essentially the color coded density maps where there is a lot of
+traffic within a small space on the graph. This could be because many frames with the same ID came in rapid fire or it could be because many
+frames with similar IDs came in very close to each other - or both.</p>
+<p>The general point of this window is to show how active the bus is at any given point in time and which IDs are most active (they’ll create
+bright streaks in the background color). There isn’t a lot that can be done to modify the functionality of this window. All that can be done is
+zooming and panning the view. If you get the view too messed up the R key will reset the view back to standard. As with the Graphing Window, it is
+possible to select just the X or Y axis and zoom/pan that axis without affecting the other one. To do so, click on the axis marks of the axis you’d like
+to independently control. To control both again click in the graph itself.</p>
+</div>
+
+
+          </div>
+      </div>
+      <div class="clearer"></div>
+    </div>
+  </body>
+</html>