Doxygen: use MARKDOWN_ID_STYLE = GITHUB (#491)

This allows linking to subsections of a tutorial.

Signed-off-by: Steve Peters <[email protected]>

Author: scpeters

doc/doxygen/api.in

@@ -319,6 +319,17 @@ EXTENSION_MAPPING      =
 
 MARKDOWN_SUPPORT       = YES
 
+# The MARKDOWN_ID_STYLE tag can be used to specify the algorithm used to
+# generate identifiers for the Markdown headings.
+# Note: Every identifier is unique. Possible values are:
+# DOXYGEN use a fixed 'autotoc_md' string followed by a sequence number
+# starting at 0 and
+# GITHUB use the lower case version of title with any whitespace replaced by
+# '-' and punctuation characters removed.
+# The default value is: DOXYGEN.
+
+MARKDOWN_ID_STYLE      = GITHUB
+
 # When the TOC_INCLUDE_HEADINGS tag is set to a non-zero value, all headings up
 # to that level are automatically included in the table of contents, even if
 # they do not have an id attribute.