[r=menno.smits] Comment improvements relating to upgrades
[r=menno.smits] Comment improvements relating to upgrades

A comment correction and a comment addition relating to different bits
of upgrade infrastructure (I've been learning how juju upgrades work).

https://codereview.appspot.com/92700043/

R=fwereade, wwitzel3
anastasiamac/juju,cloud-green/juju,howbazaar/juju,frankban/juju,davecheney/juju,mhilton/juju,mhilton/juju-juju,tych0/juju,mhilton/juju,mhilton/juju-juju,mattyw/juju,dimitern/juju,frankban/juju-tmp,bz2/juju,reedobrien/juju,marcmolla/juju,alesstimec/juju,bz2/juju,bogdanteleaga/juju,frankban/juju,ericsnowcurrently/juju,mjs/juju,gabriel-samfira/juju,perrito666/juju,tasdomas/juju,alesstimec/juju,bogdanteleaga/juju,axw/juju,sinzui/juju,mjs/juju,mikemccracken/juju,macgreagoir/juju,axw/juju,frobware/juju,kat-co/juju,anastasiamac/juju,Altoros/juju-vmware,mjs/juju,bz2/juju,marcoceppi/juju,perrito666/juju,howbazaar/juju,perrito666/juju,alesstimec/juju,mattyw/juju,thomnico/juju,mjs/juju,cmars/juju,sinzui/juju,voidspace/juju,frankban/juju,frobware/juju,bac/juju,davecheney/juju,tsakas/juju,mjs/juju,mikemccracken/juju,cmars/juju,Altoros/juju-cloudsigma,thomnico/juju,jrwren/juju,waigani/juju,ericsnowcurrently/juju,tych0/juju,bac/juju,mhilton/juju-juju,cloud-green/juju,frankban/juju,bz2/juju,rogpeppe/juju,davecheney/juju,mikemccracken/juju,AdamIsrael/juju,howbazaar/juju,Altoros/juju-vmware,tych0/juju,mjs/juju,tsakas/juju,frankban/juju-tmp,howbazaar/juju,anastasiamac/juju,bac/juju,gabriel-samfira/juju,tasdomas/juju,frankban/juju-tmp,reedobrien/juju,mhilton/juju,mikemccracken/juju,marcoceppi/juju,Altoros/juju-cloudsigma,wwitzel3/juju,axw/juju,dooferlad/juju,reedobrien/juju,ericsnowcurrently/juju,sinzui/juju,thomnico/juju,makyo/juju,dooferlad/juju,AdamIsrael/juju,cherylj/juju,frankban/juju,mattyw/juju,cloud-green/juju,anastasiamac/juju,gabriel-samfira/juju,gabriel-samfira/juju,bz2/juju,fwereade/juju,macgreagoir/juju,cherylj/juju,rogpeppe/juju,sinzui/juju,kat-co/juju,macgreagoir/juju,waigani/juju,marcmolla/juju,bogdanteleaga/juju,cmars/juju,waigani/juju,alesstimec/juju,dimitern/juju,rogpeppe/juju,tasdomas/juju,tych0/juju,marcoceppi/juju,davecheney/juju,mjs/juju,thomnico/juju,fwereade/juju,cherylj/juju,dooferlad/juju,marcmolla/juju,bac/juju,dimitern/juju,wwitzel3/juju,gabriel-samfira/juju,makyo/juju,tasdomas/juju,voidspace/juju,alesstimec/juju,perrito666/juju,ericsnowcurrently/juju,dimitern/juju,Altoros/juju-cloudsigma,ericsnowcurrently/juju,fwereade/juju,cherylj/juju,makyo/juju,cmars/juju,frobware/juju,perrito666/juju,reedobrien/juju,voidspace/juju,axw/juju,marcoceppi/juju,AdamIsrael/juju,Altoros/juju-vmware,reedobrien/juju,kat-co/juju,kat-co/juju,mhilton/juju-juju,howbazaar/juju,macgreagoir/juju,jrwren/juju,marcmolla/juju,fwereade/juju,tsakas/juju,marcmolla/juju,AdamIsrael/juju,frankban/juju-tmp,jrwren/juju,Altoros/juju-vmware,kat-co/juju,dooferlad/juju,mhilton/juju,mikemccracken/juju,anastasiamac/juju,voidspace/juju,axw/juju,cloud-green/juju,makyo/juju,macgreagoir/juju,dooferlad/juju,Altoros/juju-cloudsigma,wwitzel3/juju,mattyw/juju,bac/juju,dimitern/juju,tsakas/juju,wwitzel3/juju,waigani/juju,bogdanteleaga/juju