Add doxygen package
doxygen: use latest git version

This is due to the fact, that the --prefix option to configure was only added
after the latest release 1.8.6 was out:

https://github.com/doxygen/doxygen/commit/bc7e6301e2d1474592f6cd6cc07624852d1b5016
doxygen: add the Bison dependency
Merge pull request #200 from hashdist/doxygen

Doxygen