Small doc updates

* Doc system doesn't understand </li>
* Add docstring for mathics.builtin

Author: rocky

mathics/builtin/__init__.py

@@ -1,4 +1,9 @@
 # -*- coding: utf-8 -*-
+"""
+Mathics Built-in Functions and Variables.
+
+Mathics has over a thousand Built-in Functions and variables, all of which are defined here.
+"""
 
 import glob
 import importlib

mathics/builtin/drawing/plot.py

@@ -2283,9 +2283,9 @@ class Plot3D(_Plot3D):
 
     Plot3D has the same options as Graphics3D, in particular:
     <ul>
-    <li>Mesh</li>
-    <li>PlotPoints</li>
-    <li>MaxRecursion</li>
+    <li>Mesh
+    <li>PlotPoints
+    <li>MaxRecursion
     </ul>
 
 

mathics/builtin/graphics.py

@@ -433,15 +433,15 @@ class Graphics(Builtin):
     Options include:
 
     <ul>
-      <li>Axes</li>
-      <li>TicksStyle</li>
-      <li>AxesStyle</li>
-      <li>LabelStyle</li>
-      <li>AspectRatio</li>
-      <li>PlotRange</li>
-      <li>PlotRangePadding</li>
-      <li>ImageSize</li>
-      <li>Background</li>
+      <li>Axes
+      <li>TicksStyle
+      <li>AxesStyle
+      <li>LabelStyle
+      <li>AspectRatio
+      <li>PlotRange
+      <li>PlotRangePadding
+      <li>ImageSize
+      <li>Background
     </ul>
 
     >> Graphics[{Blue, Line[{{0,0}, {1,1}}]}]

mathics/builtin/optiondoc.py

@@ -179,10 +179,10 @@ class PlotRange(Builtin):
       <dd>is an option for 'Plot' that gives the range of coordinates to include in a plot.
     </dl>
     <ul>
-      <li>All all points are included.</li>
-      <li>Automatic - outlying points are dropped.</li>
-      <li>$max$ - explicit limit for each function.</li>
-      <li>{$min$, $max$} - explicit limits for $y$ (2D), $z$ (3D), or array value.s</li>
+      <li>All all points are included.
+      <li>Automatic - outlying points are dropped.
+      <li>$max$ - explicit limit for each function.
+      <li>{$min$, $max$} - explicit limits for $y$ (2D), $z$ (3D), or array values.
       <li>{{$x$_$min$, $x$_$max$}, {{$y_min}, {$y_max}} - explit limits for $x$ and $y$.
     </ul>
 
@@ -202,8 +202,8 @@ class TicksStyle(Builtin):
     </dl>
 
     <ul>
-    <li>TicksStyle gives styles for both tick marks and tick labels.</li>
-    <li>TicksStyle can be used in both two  and three-dimensional graphics.</li>
+    <li>TicksStyle gives styles for both tick marks and tick labels.
+    <li>TicksStyle can be used in both two  and three-dimensional graphics.
     <li>TicksStyle->$list$ specifies the colors of each of the axes.
     </ul>