Restore ModelUUID parameter to registration POST.
Restore ModelUUID parameter to registration POST.

This parameter is required and was somehow removed.

perrito666/juju,kat-co/juju,mjs/juju,AdamIsrael/juju,perrito666/juju,mjs/juju,dooferlad/juju,alesstimec/juju,macgreagoir/juju,frankban/juju,perrito666/juju,mikemccracken/juju,dimitern/juju,reedobrien/juju,axw/juju,ericsnowcurrently/juju,axw/juju,frankban/juju,bac/juju,gabriel-samfira/juju,howbazaar/juju,bac/juju,mikemccracken/juju,gabriel-samfira/juju,anastasiamac/juju,ericsnowcurrently/juju,bac/juju,alesstimec/juju,bz2/juju,marcmolla/juju,howbazaar/juju,reedobrien/juju,bz2/juju,AdamIsrael/juju,dooferlad/juju,ericsnowcurrently/juju,marcmolla/juju,kat-co/juju,perrito666/juju,waigani/juju,reedobrien/juju,perrito666/juju,frankban/juju,ericsnowcurrently/juju,reedobrien/juju,dooferlad/juju,howbazaar/juju,AdamIsrael/juju,dooferlad/juju,bz2/juju,mikemccracken/juju,waigani/juju,kat-co/juju,axw/juju,anastasiamac/juju,howbazaar/juju,axw/juju,marcmolla/juju,reedobrien/juju,macgreagoir/juju,alesstimec/juju,axw/juju,mjs/juju,macgreagoir/juju,dimitern/juju,gabriel-samfira/juju,frankban/juju,mikemccracken/juju,mjs/juju,ericsnowcurrently/juju,macgreagoir/juju,macgreagoir/juju,alesstimec/juju,alesstimec/juju,kat-co/juju,AdamIsrael/juju,gabriel-samfira/juju,anastasiamac/juju,bac/juju,waigani/juju,dooferlad/juju,mjs/juju,gabriel-samfira/juju,waigani/juju,dimitern/juju,bz2/juju,dimitern/juju,anastasiamac/juju,mikemccracken/juju,mjs/juju,howbazaar/juju,frankban/juju,marcmolla/juju,anastasiamac/juju,marcmolla/juju,bz2/juju,mjs/juju,kat-co/juju,dimitern/juju,bac/juju