Remove obsolete \setindexsubitem macros.

Massive migration to methoddesc and memberdesc.

Logical markup as needed.

A sprinkling of index entries for flavor.
diff --git a/Doc/libjpeg.tex b/Doc/libjpeg.tex
index 745fe32..201a142 100644
--- a/Doc/libjpeg.tex
+++ b/Doc/libjpeg.tex
@@ -1,10 +1,12 @@
-\section{Built-in Module \sectcode{jpeg}}
+\section{Built-in Module \module{jpeg}}
 \label{module-jpeg}
 \bimodindex{jpeg}
 
 The module \module{jpeg} provides access to the jpeg compressor and
-decompressor written by the Independent JPEG Group. JPEG is a (draft?)
-standard for compressing pictures.  For details on jpeg or the
+decompressor written by the Independent JPEG Group%
+\index{Independent JPEG Group}%
+. JPEG is a (draft?)
+standard for compressing pictures.  For details on JPEG or the
 Independent JPEG Group software refer to the JPEG standard or the
 documentation provided with the software.
 
@@ -18,19 +20,19 @@
 \begin{funcdesc}{compress}{data, w, h, b}
 Treat data as a pixmap of width \var{w} and height \var{h}, with
 \var{b} bytes per pixel.  The data is in SGI GL order, so the first
-pixel is in the lower-left corner. This means that \code{gl.lrectread}
+pixel is in the lower-left corner. This means that \function{gl.lrectread()}
 return data can immediately be passed to \function{compress()}.
 Currently only 1 byte and 4 byte pixels are allowed, the former being
 treated as greyscale and the latter as RGB color.
 \function{compress()} returns a string that contains the compressed
-picture, in JFIF format.
+picture, in JFIF\index{JFIF} format.
 \end{funcdesc}
 
 \begin{funcdesc}{decompress}{data}
-Data is a string containing a picture in JFIF format. It returns a
-tuple \code{(\var{data}, \var{width}, \var{height},
+Data is a string containing a picture in JFIF\index{JFIF} format. It
+returns a tuple \code{(\var{data}, \var{width}, \var{height},
 \var{bytesperpixel})}.  Again, the data is suitable to pass to
-\code{gl.lrectwrite}.
+\function{gl.lrectwrite()}.
 \end{funcdesc}
 
 \begin{funcdesc}{setoption}{name, value}