update to sensornet to work with IDE > 1.0.1 and it also now works with IDE 1.5.2

Changes are in S_message.cpp and nodeconfig.cpp ... currently with my change sensornet will write to eeprom instead of update (which only calls write if necessary). This can be resolved by writing a function to compare the byte stored vs the byte in question and only make a call to write if necessary.

Hope this helps.