forms.HomepageForm: Stop users from signing up for realms they can't join.
forms.HomepageForm: Stop users from signing up for realms they can't join.

We do this check in accounts_register as well, but might as well tell the
user now not to get their hopes up.

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