Attempted to clarify usage of the \declaremodule macro somewhat;

Michael Hudson's documentation for bytecodehacks exhibits incorrect
usage.

Added some comments about how to set up the mkhowto script for use
with documents not contained in the documentation source tree.

Doc/doc/doc.tex

@@ -308,6 +308,10 @@ distribution, to create or maintain whole documents or sections.
 
   \subsection{Inline Markup}
 
+    The macros described in this section are used to mark just about
+    anything interesting in the document text.  They may be used in
+    headings (though anything involving hyperlinks should be avoided
+    there) as well as in the body text.
 
     \begin{macrodesc}{bfcode}{\p{text}}
       Like \macro{code}, but also makes the font bold-face.
@@ -501,13 +505,17 @@ distribution, to create or maintain whole documents or sections.
 \end{verbatim}
 
   \begin{macrodesc}{declaremodule}{\op{key}\p{type}\p{name}}
-    Requires two parameters: module type (standard, builtin,
-    extension), and the module name.  An optional parameter should be
-    given as the basis for the module's ``key'' used for linking to or
-    referencing the section.  The ``key'' should only be given if the
-    module's name contains any underscores, and should be the name
-    with the underscores stripped.  This should be the first thing
-    after the \macro{section} used to introduce the module.
+    Requires two parameters: module type (\samp{standard},
+    \samp{builtin}, \samp{extension}, or \samp{}), and the module
+    name.  An optional parameter should be given as the basis for the
+    module's ``key'' used for linking to or referencing the section.
+    The ``key'' should only be given if the module's name contains any
+    underscores, and should be the name with the underscores stripped.
+    Note that the \var{type} parameter must be one of the values
+    listed above or an error will be printed.  For modules which are
+    contained in packages, the fully-qualified name should be given as
+    \var{name} parameter.  This should be the first thing after the
+    \macro{section} used to introduce the module.
   \end{macrodesc}
 
   \begin{macrodesc}{platform}{\p{specifier}}
@@ -894,6 +902,16 @@ distribution, to create or maintain whole documents or sections.
 
     \begin{description}
       \item[\program{mkhowto}]
+        This is the primary script used to format third-party
+	documents.  It contains all the logic needed to ``get it
+	right.''  The proper way to use this script is to make a
+	symbolic link to it or run it in place; the actual script file 
+	must be stored as part of the documentation source tree,
+	though it may be used to format documents outside the
+	tree.  Use \program{mkhowto --help} for a list of command line 
+	options.
+
+	XXX  Need more here.
     \end{description}