Radio: Updated example.
Examples: Fixed mobility Z constraint.
minor compile fix: cCanvas related code
Graphics: Followed recent changes in cCanvas API.
Radio: Moved numChannels parameter from radio medium to ieee80211 management module.
Radio: Removed obsolete ieee80211 radio medium C++ class.
Radio: Added common transmitter/receiver parameters to ieee80211 radio.
Radio: Merged ScalarRadio into Ieee80211Radio.

BTW, there was nothing scalar specific in ScalarRadio.
Radio: Followed recent renames around *RadioSignal*.
Removed canvas related ifdefs.

This is no longer necessary with the release of omnetpp 4.5.
Test: Changed to run all tests at once.
Radio: Ported breakpoint path loss model from mixim.
Radio: Ported UWBIR stochastic path loss model from mixim.
Radio: Initial port of ieee802.15.4 transmitter from mixim.
NeighborCaches: get maxSpeed parameter from RadioMedium.
GridNeigborCache: removed unnecessary useMaxDimension parameter.
GridNeighborCache: throw error when try to remove a radio that does not exist.
GridNeighborCache: cosmetic.
GridNeighborCache: renamed splittingUnit to cellSize.
RadioMedium: added per radio maxInterference/CommunicationRange getters.