added debug output for sending IEEE802.15.4 frames
Define phony make targets
Merge pull request #98 from OlegHahm/802154_debugging

added debug output for sending IEEE802.15.4 frames
Merge pull request #102 from authmillenon/master

Define phony make targets
fix warnings from #62
Merge pull request #104 from OlegHahm/unused_variables

fix warnings from #62
Added development procedures and corrected License
added mailing lists and getting started information, fixed some links
Tell Doxygen to ignore __attribute__

Doxygen can't handle it properly (see
http://doxygen.10944.n7.nabble.com/struct-attribute-packed-not-working-td2666.html)
Merge pull request #107 from authmillenon/master

Tell Doxygen to ignore __attribute__