Docs: Bugpoint fixups from JF

Also dropping the `autosectionlabel_maxdepth = 1` so that I can actually use the auto section labels.
Adds warning on bash substitution on scripting intro page when talking about `yosys -p`.

docs/source/getting_started/scripting_intro.rst

@@ -26,7 +26,7 @@ of the comment is a semicolon ``;`` or a new line.
 .. code-block::
    :caption: Using the ``-p`` option
 
-   $ yosys -p "read_verilog fifo.v; :this is a comment; prep"
+   $ yosys -p 'read_verilog fifo.v; :this is a comment; prep'
 
 .. warning::
 
@@ -42,6 +42,13 @@ will be raised by Yosys.  `exec` provides a much more flexible way of executing
 commands, allowing the output to be logged and more control over when to
 generate errors.
 
+.. warning::
+
+   Take care when using the ``yosys -p`` option.  Some shells such as bash will
+   perform substitution options inside of a double quoted string, such as ``!``
+   for history substitution and ``$`` for variable substitution; single quotes
+   should be used instead to pass the string to Yosys without substitution.
+
 The synthesis starter script
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~