add ColorPlug class and demo code
remove foating point from the public ColorPlug API

not sure yet about overflow in integer replacement code, these changes
might not have the same dynamic range as the original code
Fix a few compile errors against avr-gcc 4.7 on ubuntu.
"variable ‘helpText1’ must be const in order to be put into read-only section by means of ‘__attribute__((progmem))’"
Merge pull request #31 from Vliegendehuiskat/master

Fix 3 compile errors simmilar to this one.
quick test, pls ignore
clean up
add serial blink demo
add p1scanner demo sketch
fix several outdated URLs
start up with LED turned off
changed default PIR to active low, and renamded to PIR_INVERTED
fix stale URL
add announcer sketch
add rf12_multi to enable reception of announcer packets
undo RF12 and RF12demo change, node 31 already sees announcer packets
cleanup
fix activity led (whoops, debug leftover?)
turn activity led off on power-up
add sleep mode command
add slowLogger sketch