Improve formatting, adjust indenting for proper doxygen output.

Doxygen has changed in version 1.8.x, such that some (or all?) formatting
commands in lines with more than 3 spaces at the beginning of the line
are ignored (displayed verbatim). 


git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3@10315 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

documentation/src/development.dox

@@ -104,7 +104,7 @@ Gizmo.cxx:
   int popup_gizmo(...);
 \endverbatim
 
-<H3>Comments Within Doxygen Comment Blocks:</H3>
+<H3>Comments Within Doxygen Comment Blocks</H3>
 
 You can use HTML comment statements to embed comments in doxygen comment blocks.
 These comments will not be visible in the generated document.
@@ -122,7 +122,13 @@ will be shown as:
     This will be visible again.
 
 
-<H3>Different Headlines:</H3>
+<H3>Different Headlines</H3>
+
+You can use HTML tags \<H1> ... \<H4> for headlines with different sizes.
+As of doxygen 1.8.x there must not be more than three spaces at the
+beginning of the line for this to work. Currently (doxygen 1.8.6)
+there seems to be no difference in the font sizes of \<H3> and \<H4>
+in the pdf output, whereas the html output uses different font sizes.
 
 \code
    <H1>Headline in big text (H1)</H1>
@@ -150,7 +156,7 @@ This will appear in the document:
     &quot;, &uuml;, &ccedil;, &Ccedil;, but not all HTML quoting characters.
 
 For further informations about HTML quoting characters see
-    \b http://www.doxygen.org/htmlcmds.html
+    <br> \b http://www.doxygen.org/htmlcmds.html
 
 Alternatively you can use \b UTF-8 encoding within Doxygen comments.
 
@@ -190,7 +196,7 @@ at its top.
 
 This section is
   \code
-	\section development_structure Document structure
+	\section development_structure Document Structure
   \endcode
 
 The following section is
@@ -212,7 +218,7 @@ Links to other documents and external links can be embedded with
 \code
 
 -   see chapter \ref unicode creates a link to the named chapter
-    unicode that has been created with a \page statement.
+    unicode that has been created with a \\page statement.
 
 -   For further informations about quoting see
     http://www.doxygen.org/htmlcmds.html
@@ -245,8 +251,8 @@ to provide a paragraph title and also to indent a paragraph. Unfortunately
 \b \\par won't do what you expect if you want to have doxygen links and
 sometimes html tags don't work either.
 
-  <!-- use verbatim rather than code to avoid links to code reference -->
+<!-- use verbatim rather than code to avoid links to code reference -->
-  \verbatim
+\verbatim
   \par Normal Paragraph with title
 
   This paragraph will have a title, but because there is a blank line
@@ -268,7 +274,7 @@ sometimes html tags don't work either.
   Fl_Widget::draw() links and &quot;html&quot; tags work<br>
   \par
   Use a single line ending with <br> for complicated paragraph titles.
-  \endverbatim
+\endverbatim
 
 The above code produces the following paragraphs: