docs/utime: Add docs for ticks_add(), improvements for other ticks_*().
docs/utime: Add docs for ticks_add(), improvements for other ticks_*().

mhoffma/micropython,tobbad/micropython,cwyark/micropython,pozetroninc/micropython,blazewicz/micropython,pozetroninc/micropython,AriZuu/micropython,jmarcelino/pycom-micropython,chrisdearman/micropython,toolmacher/micropython,chrisdearman/micropython,HenrikSolver/micropython,oopy/micropython,dmazzella/micropython,MrSurly/micropython-esp32,torwag/micropython,HenrikSolver/micropython,bvernoux/micropython,pramasoul/micropython,toolmacher/micropython,toolmacher/micropython,micropython/micropython-esp32,chrisdearman/micropython,tralamazza/micropython,kerneltask/micropython,lowRISC/micropython,pramasoul/micropython,puuu/micropython,MrSurly/micropython-esp32,SHA2017-badge/micropython-esp32,henriknelson/micropython,tobbad/micropython,selste/micropython,pfalcon/micropython,bvernoux/micropython,lowRISC/micropython,bvernoux/micropython,henriknelson/micropython,swegener/micropython,adafruit/circuitpython,MrSurly/micropython,TDAbboud/micropython,TDAbboud/micropython,hiway/micropython,adafruit/micropython,swegener/micropython,henriknelson/micropython,hiway/micropython,Timmenem/micropython,deshipu/micropython,chrisdearman/micropython,matthewelse/micropython,cwyark/micropython,adafruit/micropython,adafruit/circuitpython,Timmenem/micropython,mhoffma/micropython,TDAbboud/micropython,micropython/micropython-esp32,HenrikSolver/micropython,MrSurly/micropython,Peetz0r/micropython-esp32,torwag/micropython,alex-robbins/micropython,tuc-osg/micropython,hiway/micropython,mhoffma/micropython,tuc-osg/micropython,henriknelson/micropython,oopy/micropython,pozetroninc/micropython,alex-robbins/micropython,infinnovation/micropython,mhoffma/micropython,infinnovation/micropython,chrisdearman/micropython,jmarcelino/pycom-micropython,bvernoux/micropython,dmazzella/micropython,PappaPeppar/micropython,Peetz0r/micropython-esp32,micropython/micropython-esp32,HenrikSolver/micropython,dmazzella/micropython,oopy/micropython,trezor/micropython,pozetroninc/micropython,AriZuu/micropython,tuc-osg/micropython,pozetroninc/micropython,SHA2017-badge/micropython-esp32,adafruit/circuitpython,tobbad/micropython,deshipu/micropython,ryannathans/micropython,SHA2017-badge/micropython-esp32,trezor/micropython,swegener/micropython,hiway/micropython,puuu/micropython,swegener/micropython,matthewelse/micropython,jmarcelino/pycom-micropython,PappaPeppar/micropython,pramasoul/micropython,deshipu/micropython,matthewelse/micropython,ryannathans/micropython,henriknelson/micropython,selste/micropython,ryannathans/micropython,jmarcelino/pycom-micropython,micropython/micropython-esp32,pfalcon/micropython,swegener/micropython,kerneltask/micropython,torwag/micropython,alex-robbins/micropython,PappaPeppar/micropython,Peetz0r/micropython-esp32,pfalcon/micropython,hiway/micropython,selste/micropython,adafruit/circuitpython,alex-robbins/micropython,adafruit/circuitpython,cwyark/micropython,lowRISC/micropython,MrSurly/micropython-esp32,mhoffma/micropython,selste/micropython,SHA2017-badge/micropython-esp32,kerneltask/micropython,adafruit/micropython,oopy/micropython,tobbad/micropython,deshipu/micropython,TDAbboud/micropython,infinnovation/micropython,AriZuu/micropython,MrSurly/micropython-esp32,toolmacher/micropython,pramasoul/micropython,tuc-osg/micropython,AriZuu/micropython,Timmenem/micropython,MrSurly/micropython-esp32,trezor/micropython,kerneltask/micropython,Timmenem/micropython,kerneltask/micropython,alex-robbins/micropython,ryannathans/micropython,cwyark/micropython,trezor/micropython,lowRISC/micropython,matthewelse/micropython,infinnovation/micropython,Peetz0r/micropython-esp32,jmarcelino/pycom-micropython,toolmacher/micropython,tralamazza/micropython,AriZuu/micropython,pramasoul/micropython,bvernoux/micropython,adafruit/micropython,selste/micropython,pfalcon/micropython,puuu/micropython,dmazzella/micropython,MrSurly/micropython,blazewicz/micropython,Timmenem/micropython,puuu/micropython,SHA2017-badge/micropython-esp32,MrSurly/micropython,adafruit/micropython,tobbad/micropython,tralamazza/micropython,puuu/micropython,TDAbboud/micropython,HenrikSolver/micropython,blazewicz/micropython,torwag/micropython,cwyark/micropython,torwag/micropython,deshipu/micropython,lowRISC/micropython,pfalcon/micropython,infinnovation/micropython,blazewicz/micropython,tuc-osg/micropython,PappaPeppar/micropython,oopy/micropython,matthewelse/micropython,matthewelse/micropython,trezor/micropython,blazewicz/micropython,adafruit/circuitpython,tralamazza/micropython,MrSurly/micropython,PappaPeppar/micropython,ryannathans/micropython,micropython/micropython-esp32,Peetz0r/micropython-esp32