doc/Doxyfile: remove obsolete options with the default values

FORMULA_FONTSIZE       = 10

# Use the FORMULA_TRANSPARENT tag to determine whether or not the images

# generated for formulas are transparent PNGs. Transparent PNGs are not

# supported properly for IE 6.0, but are supported on all modern browsers.

#

# Note that when changing this option you need to delete any form_*.png files in

# the HTML output directory before the changes have effect.

# The default value is: YES.

# This tag requires that the tag GENERATE_HTML is set to YES.

FORMULA_TRANSPARENT    = YES

# Enable the USE_MATHJAX option to render LaTeX formulas using MathJax (see

# http://www.mathjax.org) which uses client side Javascript for the rendering

# instead of using pre-rendered bitmaps. Use this if you do not have LaTeX

LATEX_HIDE_INDICES     = NO

# If the LATEX_SOURCE_CODE tag is set to YES then doxygen will include source

# code with syntax highlighting in the LaTeX output.

#

# Note that which sources are shown also depends on other settings such as

# SOURCE_BROWSER.

# The default value is: NO.

# This tag requires that the tag GENERATE_LATEX is set to YES.

LATEX_SOURCE_CODE      = NO

# The LATEX_BIB_STYLE tag can be used to specify the style to use for the

# bibliography, e.g. plainnat, or ieeetr. See

# http://en.wikipedia.org/wiki/BibTeX and \cite for more info.

RTF_EXTENSIONS_FILE    =

# If the RTF_SOURCE_CODE tag is set to YES then doxygen will include source code

# with syntax highlighting in the RTF output.

#

# Note that which sources are shown also depends on other settings such as

# SOURCE_BROWSER.

# The default value is: NO.

# This tag requires that the tag GENERATE_RTF is set to YES.

RTF_SOURCE_CODE        = NO

#---------------------------------------------------------------------------

# Configuration options related to the man page output

#---------------------------------------------------------------------------

DOCBOOK_OUTPUT         = docbook

# If the DOCBOOK_PROGRAMLISTING tag is set to YES, doxygen will include the

# program listings (including syntax highlighting and cross-referencing

# information) to the DOCBOOK output. Note that enabling this will significantly

# increase the size of the DOCBOOK output.

# The default value is: NO.

# This tag requires that the tag GENERATE_DOCBOOK is set to YES.

DOCBOOK_PROGRAMLISTING = NO

#---------------------------------------------------------------------------

# Configuration options for the AutoGen Definitions output

#---------------------------------------------------------------------------

# Configuration options related to the dot tool

#---------------------------------------------------------------------------

# If the CLASS_DIAGRAMS tag is set to YES, doxygen will generate a class diagram

# (in HTML and LaTeX) for classes with base or super classes. Setting the tag to

# NO turns the diagrams off. Note that this option also works with HAVE_DOT

# disabled, but it is recommended to install and use dot, since it yields more

# powerful graphs.

# The default value is: YES.

CLASS_DIAGRAMS         = YES

# You can define message sequence charts within doxygen comments using the \msc

# command. Doxygen will then run the mscgen tool (see:

# http://www.mcternan.me.uk/mscgen/)) to produce the chart and insert it in the

DOT_NUM_THREADS        = 0

# When you want a differently looking font in the dot files that doxygen

# generates you can specify the font name using DOT_FONTNAME. You need to make

# sure dot is able to find the font, which can be done by putting it in a

# standard location or by setting the DOTFONTPATH environment variable or by

# setting DOT_FONTPATH to the directory containing the font.

# The default value is: Helvetica.

# This tag requires that the tag HAVE_DOT is set to YES.

DOT_FONTNAME           = Helvetica

# The DOT_FONTSIZE tag can be used to set the size (in points) of the font of

# dot graphs.

# Minimum value: 4, maximum value: 24, default value: 10.

# This tag requires that the tag HAVE_DOT is set to YES.

DOT_FONTSIZE           = 10

# By default doxygen will tell dot to use the default font as specified with

# DOT_FONTNAME. If you specify a different font using DOT_FONTNAME you can set

# the path where dot can find it using this tag.

MAX_DOT_GRAPH_DEPTH    = 2

# Set the DOT_TRANSPARENT tag to YES to generate images with a transparent

# background. This is disabled by default, because dot on Windows does not seem

# to support this out of the box.

#

# Warning: Depending on the platform used, enabling this option may lead to

# badly anti-aliased labels on the edges of a graph (i.e. they become hard to

# read).

# The default value is: NO.

# This tag requires that the tag HAVE_DOT is set to YES.

DOT_TRANSPARENT        = NO

# Set the DOT_MULTI_TARGETS tag to YES to allow dot to generate multiple output

# files in one run (i.e. multiple -o and -T options on the command line). This

# makes dot run faster, but since only newer versions of dot (>1.8.10) support