* doc/Doxyfile.in: Make use of bibliography.

	* doc/bibliography.dox: Add references.

	* doc/DoxygenLayout.xml,
	* doc/doc.css,
	* doc/doxygen.css,
	* doc/footer.html,
	* doc/header.html,
	* doc/subdoc_footer.html: Improve rendering.

	* doc/Makefile.am,
	* doc/header.html,
	* doc/mainpage.dox: Fix paths and disable the use of installdox
	(deprecated)

	* doc/doxygen.css,
	* doc/footer.html: Fix footer.

	* configure.ac: Add new makefiles.

	* doc/.gitignore,
	* doc/Doxyfile.in,
	* doc/DoxygenLayout.xml,
	* doc/Makefile.am,
	* doc/doxygen.css,
	* doc/footer.html,
	* doc/header.html,
	* doc/logo.jpg,
	* doc/mainpage.hh,
	* doc/olena.qhcp,
	* doc/subdoc_footer.html: New.