Create lister.py.
Create lister.py.

Make module tools/lister.py which lists all files in a directory
tracked by git.  This is done because lister.py will be used by other
scripts in the future which have to introspect files in the repository,
like linters, static code checkers, etc.

timabbott/zulip,rht/zulip,peiwei/zulip,eeshangarg/zulip,brainwane/zulip,JPJPJPOPOP/zulip,zacps/zulip,JPJPJPOPOP/zulip,susansls/zulip,verma-varsha/zulip,punchagan/zulip,dwrpayne/zulip,reyha/zulip,kou/zulip,dawran6/zulip,Vallher/zulip,verma-varsha/zulip,arpith/zulip,cosmicAsymmetry/zulip,sonali0901/zulip,brainwane/zulip,ryanbackman/zulip,susansls/zulip,andersk/zulip,tommyip/zulip,sharmaeklavya2/zulip,jackrzhang/zulip,Juanvulcano/zulip,sonali0901/zulip,ahmadassaf/zulip,peiwei/zulip,mahim97/zulip,blaze225/zulip,Vallher/zulip,dattatreya303/zulip,sharmaeklavya2/zulip,shubhamdhama/zulip,zulip/zulip,sonali0901/zulip,rht/zulip,vaidap/zulip,Frouk/zulip,showell/zulip,Galexrt/zulip,rht/zulip,SmartPeople/zulip,AZtheAsian/zulip,punchagan/zulip,arpith/zulip,eeshangarg/zulip,joyhchen/zulip,mahim97/zulip,timabbott/zulip,zacps/zulip,arpith/zulip,vabs22/zulip,susansls/zulip,isht3/zulip,zacps/zulip,tommyip/zulip,Jianchun1/zulip,krtkmj/zulip,zulip/zulip,dhcrzf/zulip,Diptanshu8/zulip,punchagan/zulip,vabs22/zulip,rishig/zulip,sup95/zulip,umkay/zulip,grave-w-grave/zulip,christi3k/zulip,grave-w-grave/zulip,ahmadassaf/zulip,paxapy/zulip,eeshangarg/zulip,sharmaeklavya2/zulip,Juanvulcano/zulip,christi3k/zulip,kou/zulip,TigorC/zulip,sup95/zulip,dattatreya303/zulip,susansls/zulip,christi3k/zulip,tommyip/zulip,Vallher/zulip,souravbadami/zulip,vabs22/zulip,grave-w-grave/zulip,aakash-cr7/zulip,Juanvulcano/zulip,dhcrzf/zulip,sup95/zulip,umkay/zulip,amyliu345/zulip,kou/zulip,reyha/zulip,aakash-cr7/zulip,vaidap/zulip,brockwhittaker/zulip,peguin40/zulip,blaze225/zulip,umkay/zulip,JPJPJPOPOP/zulip,Juanvulcano/zulip,joyhchen/zulip,ahmadassaf/zulip,Galexrt/zulip,vikas-parashar/zulip,jphilipsen05/zulip,dattatreya303/zulip,dwrpayne/zulip,jackrzhang/zulip,krtkmj/zulip,j831/zulip,cosmicAsymmetry/zulip,Vallher/zulip,TigorC/zulip,andersk/zulip,isht3/zulip,dawran6/zulip,souravbadami/zulip,amyliu345/zulip,jackrzhang/zulip,Vallher/zulip,isht3/zulip,verma-varsha/zulip,grave-w-grave/zulip,showell/zulip,Jianchun1/zulip,mohsenSy/zulip,brockwhittaker/zulip,reyha/zulip,rht/zulip,aakash-cr7/zulip,krtkmj/zulip,timabbott/zulip,kou/zulip,joyhchen/zulip,aakash-cr7/zulip,Juanvulcano/zulip,JPJPJPOPOP/zulip,samatdav/zulip,vaidap/zulip,dwrpayne/zulip,niftynei/zulip,sup95/zulip,hackerkid/zulip,jphilipsen05/zulip,jphilipsen05/zulip,synicalsyntax/zulip,ryansnowboarder/zulip,ryansnowboarder/zulip,dawran6/zulip,ahmadassaf/zulip,timabbott/zulip,Jianchun1/zulip,vaidap/zulip,Galexrt/zulip,zulip/zulip,Jianchun1/zulip,tommyip/zulip,niftynei/zulip,brainwane/zulip,timabbott/zulip,amanharitsh123/zulip,dhcrzf/zulip,JPJPJPOPOP/zulip,amanharitsh123/zulip,Diptanshu8/zulip,Diptanshu8/zulip,tommyip/zulip,zulip/zulip,dattatreya303/zulip,synicalsyntax/zulip,PhilSk/zulip,vabs22/zulip,AZtheAsian/zulip,jainayush975/zulip,souravbadami/zulip,samatdav/zulip,arpith/zulip,Juanvulcano/zulip,niftynei/zulip,zacps/zulip,dhcrzf/zulip,jainayush975/zulip,jrowan/zulip,synicalsyntax/zulip,ryansnowboarder/zulip,Galexrt/zulip,peiwei/zulip,reyha/zulip,Frouk/zulip,arpith/zulip,punchagan/zulip,Vallher/zulip,AZtheAsian/zulip,andersk/zulip,ryansnowboarder/zulip,KingxBanana/zulip,dwrpayne/zulip,eeshangarg/zulip,Jianchun1/zulip,jainayush975/zulip,PhilSk/zulip,jrowan/zulip,calvinleenyc/zulip,PhilSk/zulip,peiwei/zulip,vabs22/zulip,paxapy/zulip,amanharitsh123/zulip,shubhamdhama/zulip,brainwane/zulip,joyhchen/zulip,amanharitsh123/zulip,peguin40/zulip,Diptanshu8/zulip,verma-varsha/zulip,TigorC/zulip,ryanbackman/zulip,KingxBanana/zulip,hackerkid/zulip,amyliu345/zulip,kou/zulip,synicalsyntax/zulip,Frouk/zulip,cosmicAsymmetry/zulip,samatdav/zulip,paxapy/zulip,amyliu345/zulip,blaze225/zulip,TigorC/zulip,krtkmj/zulip,KingxBanana/zulip,mahim97/zulip,dhcrzf/zulip,jphilipsen05/zulip,SmartPeople/zulip,dattatreya303/zulip,zulip/zulip,jrowan/zulip,showell/zulip,rht/zulip,zacps/zulip,isht3/zulip,sharmaeklavya2/zulip,sonali0901/zulip,susansls/zulip,rishig/zulip,Galexrt/zulip,AZtheAsian/zulip,zulip/zulip,cosmicAsymmetry/zulip,Galexrt/zulip,KingxBanana/zulip,shubhamdhama/zulip,paxapy/zulip,isht3/zulip,rht/zulip,vikas-parashar/zulip,j831/zulip,sonali0901/zulip,ahmadassaf/zulip,j831/zulip,zacps/zulip,brainwane/zulip,AZtheAsian/zulip,jainayush975/zulip,souravbadami/zulip,peiwei/zulip,mohsenSy/zulip,synicalsyntax/zulip,blaze225/zulip,punchagan/zulip,SmartPeople/zulip,mahim97/zulip,AZtheAsian/zulip,PhilSk/zulip,krtkmj/zulip,ryanbackman/zulip,peguin40/zulip,andersk/zulip,christi3k/zulip,synicalsyntax/zulip,aakash-cr7/zulip,aakash-cr7/zulip,ryansnowboarder/zulip,mahim97/zulip,showell/zulip,Diptanshu8/zulip,tommyip/zulip,cosmicAsymmetry/zulip,niftynei/zulip,jackrzhang/zulip,j831/zulip,paxapy/zulip,mohsenSy/zulip,peiwei/zulip,reyha/zulip,hackerkid/zulip,eeshangarg/zulip,souravbadami/zulip,ahmadassaf/zulip,verma-varsha/zulip,tommyip/zulip,punchagan/zulip,dhcrzf/zulip,souravbadami/zulip,umkay/zulip,blaze225/zulip,dawran6/zulip,dhcrzf/zulip,vikas-parashar/zulip,grave-w-grave/zulip,grave-w-grave/zulip,dwrpayne/zulip,ryanbackman/zulip,rht/zulip,shubhamdhama/zulip,susansls/zulip,sharmaeklavya2/zulip,mohsenSy/zulip,isht3/zulip,andersk/zulip,andersk/zulip,Diptanshu8/zulip,j831/zulip,umkay/zulip,samatdav/zulip,verma-varsha/zulip,paxapy/zulip,Frouk/zulip,christi3k/zulip,Frouk/zulip,showell/zulip,jrowan/zulip,dattatreya303/zulip,shubhamdhama/zulip,peguin40/zulip,mohsenSy/zulip,eeshangarg/zulip,jainayush975/zulip,j831/zulip,mohsenSy/zulip,hackerkid/zulip,krtkmj/zulip,jackrzhang/zulip,timabbott/zulip,punchagan/zulip,ryansnowboarder/zulip,niftynei/zulip,calvinleenyc/zulip,peguin40/zulip,mahim97/zulip,vikas-parashar/zulip,TigorC/zulip,rishig/zulip,sup95/zulip,calvinleenyc/zulip,ahmadassaf/zulip,Frouk/zulip,sonali0901/zulip,rishig/zulip,dawran6/zulip,andersk/zulip,KingxBanana/zulip,vaidap/zulip,hackerkid/zulip,vikas-parashar/zulip,PhilSk/zulip,SmartPeople/zulip,ryanbackman/zulip,brockwhittaker/zulip,rishig/zulip,jackrzhang/zulip,eeshangarg/zulip,Jianchun1/zulip,brockwhittaker/zulip,brainwane/zulip,amanharitsh123/zulip,peguin40/zulip,niftynei/zulip,amanharitsh123/zulip,brockwhittaker/zulip,SmartPeople/zulip,showell/zulip,JPJPJPOPOP/zulip,rishig/zulip,amyliu345/zulip,kou/zulip,calvinleenyc/zulip,shubhamdhama/zulip,TigorC/zulip,umkay/zulip,calvinleenyc/zulip,KingxBanana/zulip,calvinleenyc/zulip,Galexrt/zulip,SmartPeople/zulip,joyhchen/zulip,rishig/zulip,hackerkid/zulip,reyha/zulip,sharmaeklavya2/zulip,hackerkid/zulip,peiwei/zulip,sup95/zulip,jrowan/zulip,shubhamdhama/zulip,kou/zulip,arpith/zulip,samatdav/zulip,dwrpayne/zulip,umkay/zulip,showell/zulip,jphilipsen05/zulip,krtkmj/zulip,christi3k/zulip,vabs22/zulip,brainwane/zulip,PhilSk/zulip,samatdav/zulip,jphilipsen05/zulip,ryanbackman/zulip,synicalsyntax/zulip,vikas-parashar/zulip,amyliu345/zulip,ryansnowboarder/zulip,vaidap/zulip,dawran6/zulip,jainayush975/zulip,cosmicAsymmetry/zulip,dwrpayne/zulip,zulip/zulip,jackrzhang/zulip,Frouk/zulip,jrowan/zulip,blaze225/zulip,Vallher/zulip,joyhchen/zulip,timabbott/zulip,brockwhittaker/zulip