[signup:form] - Refactor showSuccess and remove deprecated methods
[signup:form] - Refactor showSuccess and remove deprecated methods

DemocracyOS/app,solde9/app,CivicTechFR/DemocracyOSFR,AbraaoAlves/app,kant/app,d-cent/democracyos,mairwilliams/app,atlatszo/evoks,mbhicks90/myvotes.ca,alexproca/democracy-os,DemocracyOS/app,MareAtlantica/democracyos,DemocraciaEnRed/bahiablanca,solde9/app,PartidoDeLaRed/app,EuParticipo/Caxias,huulbaek/app,okfn-brasil/euvoto,120photo/app,josuedor/app,ben-pr-p/app,beomjae/app,josuedor/app,Nicolas-Lebreton/app,EuParticipo/Caxias,valentinchaput/app,MareAtlantica/democracyos,beomjae/app,kant/app,fonorobert/evoks,vntrp/app,piratenfraktion-nrw/app,atlatszo/evoks,radvansky-tomas/app,mbhicks90/myvotes.ca,PartidoDeLaRed/app,120photo/app,piratenfraktion-nrw/app,moustachu/democracy-os-app,dkrathi457/app,okfn-brasil/euvoto,dkrathi457/app,ManuH/app,DemocraciaEnRed/bahiablanca,ManuH/app,DemocraciaEnRed/comunas,indiofran/app,maiklaguna/app,mairwilliams/app,huulbaek/app,valentinchaput/app,radvansky-tomas/app,alexproca/democracy-os,DemocraciaEnRed/comunas,fonorobert/evoks,AbraaoAlves/app,Nicolas-Lebreton/app,indiofran/app,10Pines/app,ben-pr-p/app,vntrp/app,mxabierto/colaborativa,CivicTechFR/DemocracyOSFR,moustachu/democracy-os-app,mgarciaisaia/democracy-os-ues