add doxygen configuration

Tested on SLC6 node (provides doxygen v1.6.1 and dot)
add doxygen configuration

Tested on SLC6 node (provides doxygen v1.6.1 and dot)
Merge branch 'doxygen' of github.com:gerbaudo/SusyNtuple into doxygen
travis: add key and after_success; add run_doxygen.sh
run_doxygen: fix path
dbg run_doxygen path
run_doxygen now working, drop dbg echo
typo (LAST_COMMIT_MESSAGE->MSG) [build-doxygen]
format comments [build-doxygen]

Re-format existing comments following the doxygen syntax
Merge pull request #17 from gerbaudo/doxygen

add doxygen configuration