Add hardware_pwm() function to smoothie Pins
Add PID-loopback spindle speed control
Fix spindle PID D-term scaling
Fix mixed CRLF/LF line ends in score_cm3.h
Move systick initialization from main.cpp to Spindle.cpp
Fix SysTick_Config() so that one can set LOAD = SYSTICK_MAXCOUNT
Merge pull request #549 from PetteriAimonen/edge

Added spindle speed control module using PID feedback
update firmware.bin
Use AppendFIleStream for M500 to avoid fatlib/sdcard write bug
fix actuator position inaccuracy on pause
Merge pull request #550 from wolfmanjm/upstreamedge

fix actuator position inaccuracy on pause
Merge branch 'edge' of https://github.com/Smoothieware/Smoothieware into edge