Remove dot lexer from docs

Closes #37

docs/customization_guide.rst

@@ -14,7 +14,7 @@ The dot language defines the ``style`` attribute that can be used to modify the
 
 The following example shows how interesting visual results can be achieved with the PGF/TikZ output format. The styles are PGF/TikZ specific. See the user guide for details:
 
-.. sourcecode:: dot
+::
 
     graph G {
         node [shape=circle, fixedsize=True, width="0.2",
@@ -44,7 +44,7 @@ Changing arrow types
 
 The style attribute can be used to change arrow types. A PGF/TikZ example:
 
-.. sourcecode:: dot
+::
 
     digraph G {
         graph [mindist=0.5];
@@ -77,7 +77,7 @@ You can also set the default arrow style by using the ``--graphstyle`` option or
 
 A PSTricks example:
 
-.. sourcecode:: dot
+::
 
     digraph G {
         d2tdocpreamble="\usepackage{pstricks-add}";
@@ -124,7 +124,7 @@ When you specify a ``lblstyle`` attribute, the style will be given as a paramete
 
 Example:
 
-.. sourcecode:: dot
+::
 
     digraph G {
         node [shape=circle];
@@ -175,7 +175,7 @@ With the ``--tikzedgelabel`` option you can bypass the XDOT edge label placement
 
 Example:
 
-.. sourcecode:: dot
+::
 
     graph G {
         mindist = 0.5;
@@ -225,7 +225,7 @@ The ``topath`` edge attribute offers a way to override the edges drawn by Graphv
 
 Example:
 
-.. sourcecode:: dot
+::
 
     digraph G {
         mindist = 0.5;
@@ -258,7 +258,7 @@ The generated edge drawing code is:
 
 Here is a larger example that uses the ``automata`` library:
 
-.. sourcecode:: dot
+::
 
     digraph G {
         d2tdocpreamble = "\usetikzlibrary{automata}";

docs/tipsandtricks.rst

@@ -60,7 +60,7 @@ So instead of typing::
 
 each time, use ``d2toptions`` like this:
 
-.. sourcecode:: dot
+::
 
     digraph G {
         d2toptions ="-tikz -tmath --tikzedgelabels";
@@ -76,7 +76,7 @@ Use the tikz output format for maximum flexibility
 
 The difference between the ``pgf`` and ``tikz`` output formats is best shown with an example. Consider the following graph:
 
-.. sourcecode:: dot
+::
 
     graph G {
         mindist = 0.5;

docs/usage_guide.rst

@@ -261,7 +261,7 @@ Label examples
 
 Consider the following graph:
 
-.. sourcecode:: dot
+::
 
     digraph G {
         a_1-> a_2 -> a_3 -> a_1;
@@ -278,7 +278,7 @@ gives the result shown in the left hand side of the figure below. The default re
 
 Example of using ``texlbl``:
 
-.. sourcecode:: dot
+::
 
     digraph G {
         a_1 [texlbl="$\frac{\gamma}{x^2}$"];
@@ -290,7 +290,7 @@ Example of using ``texlbl``:
 
 Example of using the ``texmode`` attribute:
 
-.. sourcecode:: dot
+::
 
     digraph G {
         a_1 [texlbl="$\frac{\gamma}{2x^2+y^3}$"];
@@ -331,7 +331,7 @@ Dot2tex relies on the xdot format for drawing nodes and placing node labels. The
 
 Here is an example graph where it is necessary to use the ``valignmode`` option:
 
-.. sourcecode:: dot
+::
 
     digraph G {
         node0 [label="{left|right}", shape=record];
@@ -367,7 +367,7 @@ PSTricks users have to use the ``--alingstr`` option::
 
 The result is better, but to get even better alignment you have to change the node font size. Graphviz' default font size is 14pt, which is larger than the typical 10pt or 11pt used in LaTeX documents. By changing the node font size to 10pt we can trick Graphviz to give us a better alignment:
 
-.. sourcecode:: dot
+::
 
     digraph G {
         node [fontsize=10];
@@ -415,7 +415,7 @@ Examples
 
 Consider the following graph:
 
-.. sourcecode:: dot
+::
 
     digraph G {
         node [shape=circle];
@@ -453,7 +453,7 @@ The resulting graph now has correctly sized nodes and edge labels:
 
 Modifying node sizes using the ``widht/height`` and ``margin`` attributes can be a bit counterintuitive. A few examples will hopefully make it clearer:
 
-.. sourcecode:: dot
+::
 
     digraph G {
         node [shape=rectangle];