Merged in chrishamm's changes to Network, PrintMonitor, and his support
for firmware updates from SD card
Fixed print monitor issue that threw out the layer count and time
estimates when there was an initial extruder priming move in the start
gcode
Enabled gcc compiler warnings. Fixed over 100 warnings including at
least one actual and several potential bugs.
Simplified delta calibration code and added X and Y parameters to M665
command
Implemented chamber temperature commands (thanks chrishamm)
Merged in zpl's latest changes to Network and Print Monitor modules,
providing DHCP and Netbios name support
Added command M999 S4321 to unlock flash memory, reset and boot to BOSSA
port
Z dive height is now relative to Z probe trigger height and default is
reduced to 3mm
Added experimental support for acoustic probe for delta printers
Bug fix: firmware once again prevents Z homing before X and Y are homed,
if the Z probe is used for Z homing
Various code tidying
Added modified lwip files that were missed from last checkin
Fixed incorrect JSON format in response to the rr_files command when no
files were found
Enabled hardware debounce filter on cooling fan RPM pin to get a correct
and stable readout
Changed network startup to avoid long delay if no network cable is
connected
Enable DHCP support if IP address is configured as 0.0.0.0 (not working
yet)
Move thermistor parameters to M305, added parameter to configure series
resistance
Added B and W PID parameters
