Fixed bug that caused the cooling fan PWM frequency to be 165kHz. It is
now 25kHz.
Fan RPM is now included in the web interface status response (thanks
zpl).
Many more error messages are now reported to the web interface as well
as the USB interface.
Interrupt-driven network timer task to better cope with slow SD card
writes (thanks zpl)
Module SamNonDuePin is now used for all digital and PWM pin I/O.
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
Removed file httpd.c and moved its functions into Network.cpp. This
gives us type-checking across more interface boundaries and eliminates a
number of global functions. Also removed unused files fs.c, fsdata.c,
httpd-original.c.