py/formatfloat: Add ability to format doubles with exponents > 99.
py/formatfloat: Add ability to format doubles with exponents > 99.

For single prec, exponents never get larger than about 37.  For double
prec, exponents can be larger than 99 and need 3 bytes to format.  This
patch makes the number of bytes needed configurable.

Addresses issue #1772.

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