tests/run-tests: Add cmd line option "--heapsize".
tests/run-tests: Add cmd line option "--heapsize".

This allows you to specify the heapsize that unix will use when running
the test suite, eg: ./run-tests --heapsize 16k

turbinenreiter/micropython,lowRISC/micropython,deshipu/micropython,pramasoul/micropython,MrSurly/micropython,bvernoux/micropython,torwag/micropython,ryannathans/micropython,chrisdearman/micropython,Peetz0r/micropython-esp32,infinnovation/micropython,tobbad/micropython,adafruit/circuitpython,puuu/micropython,matthewelse/micropython,redbear/micropython,oopy/micropython,SHA2017-badge/micropython-esp32,dxxb/micropython,swegener/micropython,deshipu/micropython,alex-march/micropython,adafruit/circuitpython,tuc-osg/micropython,lowRISC/micropython,drrk/micropython,deshipu/micropython,PappaPeppar/micropython,pramasoul/micropython,trezor/micropython,matthewelse/micropython,jmarcelino/pycom-micropython,misterdanb/micropython,redbear/micropython,matthewelse/micropython,praemdonck/micropython,tobbad/micropython,jmarcelino/pycom-micropython,praemdonck/micropython,MrSurly/micropython-esp32,blazewicz/micropython,misterdanb/micropython,selste/micropython,praemdonck/micropython,emfcamp/micropython,cwyark/micropython,torwag/micropython,emfcamp/micropython,selste/micropython,selste/micropython,MrSurly/micropython-esp32,alex-march/micropython,jmarcelino/pycom-micropython,dxxb/micropython,mpalomer/micropython,pfalcon/micropython,blazewicz/micropython,tralamazza/micropython,Timmenem/micropython,Peetz0r/micropython-esp32,kerneltask/micropython,turbinenreiter/micropython,lowRISC/micropython,dmazzella/micropython,deshipu/micropython,Peetz0r/micropython-esp32,alex-robbins/micropython,dinau/micropython,chrisdearman/micropython,hiway/micropython,emfcamp/micropython,hosaka/micropython,emfcamp/micropython,Peetz0r/micropython-esp32,pfalcon/micropython,HenrikSolver/micropython,turbinenreiter/micropython,HenrikSolver/micropython,toolmacher/micropython,praemdonck/micropython,trezor/micropython,jmarcelino/pycom-micropython,matthewelse/micropython,micropython/micropython-esp32,adafruit/micropython,swegener/micropython,pramasoul/micropython,TDAbboud/micropython,micropython/micropython-esp32,toolmacher/micropython,chrisdearman/micropython,lowRISC/micropython,ryannathans/micropython,ganshun666/micropython,kerneltask/micropython,mhoffma/micropython,adafruit/micropython,tobbad/micropython,ryannathans/micropython,adafruit/micropython,infinnovation/micropython,swegener/micropython,tralamazza/micropython,kerneltask/micropython,PappaPeppar/micropython,henriknelson/micropython,adafruit/circuitpython,tuc-osg/micropython,hosaka/micropython,lowRISC/micropython,misterdanb/micropython,HenrikSolver/micropython,turbinenreiter/micropython,cwyark/micropython,oopy/micropython,dinau/micropython,torwag/micropython,alex-robbins/micropython,pramasoul/micropython,dinau/micropython,mhoffma/micropython,tobbad/micropython,Timmenem/micropython,dmazzella/micropython,oopy/micropython,hiway/micropython,puuu/micropython,alex-march/micropython,toolmacher/micropython,trezor/micropython,blazewicz/micropython,dxxb/micropython,hiway/micropython,infinnovation/micropython,henriknelson/micropython,PappaPeppar/micropython,kerneltask/micropython,pfalcon/micropython,drrk/micropython,ryannathans/micropython,kerneltask/micropython,torwag/micropython,dinau/micropython,swegener/micropython,tuc-osg/micropython,AriZuu/micropython,AriZuu/micropython,MrSurly/micropython-esp32,TDAbboud/micropython,matthewelse/micropython,toolmacher/micropython,turbinenreiter/micropython,Timmenem/micropython,tuc-osg/micropython,toolmacher/micropython,tralamazza/micropython,ganshun666/micropython,adafruit/circuitpython,mpalomer/micropython,hosaka/micropython,micropython/micropython-esp32,drrk/micropython,misterdanb/micropython,SHA2017-badge/micropython-esp32,MrSurly/micropython-esp32,oopy/micropython,pramasoul/micropython,drrk/micropython,chrisdearman/micropython,mhoffma/micropython,AriZuu/micropython,pozetroninc/micropython,dmazzella/micropython,puuu/micropython,micropython/micropython-esp32,adafruit/micropython,hiway/micropython,blazewicz/micropython,pfalcon/micropython,jmarcelino/pycom-micropython,micropython/micropython-esp32,tobbad/micropython,praemdonck/micropython,puuu/micropython,oopy/micropython,matthewelse/micropython,alex-robbins/micropython,alex-march/micropython,alex-march/micropython,henriknelson/micropython,adafruit/circuitpython,PappaPeppar/micropython,TDAbboud/micropython,infinnovation/micropython,Timmenem/micropython,misterdanb/micropython,chrisdearman/micropython,Timmenem/micropython,pfalcon/micropython,bvernoux/micropython,selste/micropython,selste/micropython,MrSurly/micropython,MrSurly/micropython,pozetroninc/micropython,TDAbboud/micropython,torwag/micropython,swegener/micropython,AriZuu/micropython,pozetroninc/micropython,MrSurly/micropython,mpalomer/micropython,SHA2017-badge/micropython-esp32,bvernoux/micropython,bvernoux/micropython,drrk/micropython,tuc-osg/micropython,dinau/micropython,hiway/micropython,AriZuu/micropython,hosaka/micropython,mpalomer/micropython,HenrikSolver/micropython,henriknelson/micropython,ganshun666/micropython,bvernoux/micropython,SHA2017-badge/micropython-esp32,blazewicz/micropython,cwyark/micropython,tralamazza/micropython,alex-robbins/micropython,Peetz0r/micropython-esp32,emfcamp/micropython,henriknelson/micropython,MrSurly/micropython,mhoffma/micropython,hosaka/micropython,puuu/micropython,ryannathans/micropython,redbear/micropython,infinnovation/micropython,alex-robbins/micropython,SHA2017-badge/micropython-esp32,mpalomer/micropython,trezor/micropython,ganshun666/micropython,adafruit/circuitpython,dxxb/micropython,ganshun666/micropython,TDAbboud/micropython,cwyark/micropython,MrSurly/micropython-esp32,deshipu/micropython,PappaPeppar/micropython,dxxb/micropython,pozetroninc/micropython,redbear/micropython,trezor/micropython,cwyark/micropython,redbear/micropython,HenrikSolver/micropython,pozetroninc/micropython,adafruit/micropython,mhoffma/micropython,dmazzella/micropython