[r=sinzui] Run unit-tests on trusty
[r=sinzui] Run unit-tests on trusty

Backport the lsb_release check to 1.16 the ensure the right deps are installed
to run unit-tests on trusty.

https://codereview.appspot.com/64000043/
gabriel-samfira/juju,ericsnowcurrently/juju,tasdomas/juju,kat-co/juju,voidspace/juju,bz2/juju,tasdomas/juju,cloud-green/juju,frankban/juju,tsakas/juju,bac/juju,mattyw/juju,jrwren/juju,AdamIsrael/juju,cloud-green/juju,ericsnowcurrently/juju,howbazaar/juju,tych0/juju,wwitzel3/juju,voidspace/juju,thomnico/juju,bac/juju,alesstimec/juju,rogpeppe/juju,dimitern/juju,mhilton/juju,davecheney/juju,bz2/juju,bogdanteleaga/juju,cmars/juju,dimitern/juju,frankban/juju,kat-co/juju,mattyw/juju,bz2/juju,sinzui/juju,fwereade/juju,marcmolla/juju,Altoros/juju-vmware,frankban/juju-tmp,tych0/juju,mjs/juju,Altoros/juju-cloudsigma,marcmolla/juju,makyo/juju,AdamIsrael/juju,bogdanteleaga/juju,marcmolla/juju,mhilton/juju-juju,AdamIsrael/juju,voidspace/juju,tych0/juju,frankban/juju,makyo/juju,frankban/juju,mikemccracken/juju,dooferlad/juju,Altoros/juju-cloudsigma,frankban/juju-tmp,anastasiamac/juju,kat-co/juju,perrito666/juju,marcoceppi/juju,gabriel-samfira/juju,reedobrien/juju,Altoros/juju-cloudsigma,tsakas/juju,reedobrien/juju,thomnico/juju,dimitern/juju,anastasiamac/juju,perrito666/juju,mhilton/juju-juju,sinzui/juju,rogpeppe/juju,wwitzel3/juju,makyo/juju,rogpeppe/juju,axw/juju,macgreagoir/juju,macgreagoir/juju,dooferlad/juju,perrito666/juju,axw/juju,frobware/juju,cmars/juju,ericsnowcurrently/juju,gabriel-samfira/juju,jrwren/juju,mhilton/juju,marcoceppi/juju,tasdomas/juju,voidspace/juju,anastasiamac/juju,cloud-green/juju,mhilton/juju-juju,macgreagoir/juju,mhilton/juju,bogdanteleaga/juju,mikemccracken/juju,bac/juju,jrwren/juju,sinzui/juju,mjs/juju,reedobrien/store,tasdomas/juju,alesstimec/juju,fwereade/juju,cherylj/juju,bac/juju,tsakas/juju,alesstimec/juju,reedobrien/juju,cherylj/juju,mikemccracken/juju,mjs/juju,dooferlad/juju,gabriel-samfira/juju,howbazaar/juju,AdamIsrael/juju,thomnico/juju,Altoros/juju-vmware,mhilton/juju-juju,dooferlad/juju,marcmolla/juju,cmars/juju,dooferlad/juju,mattyw/juju,wwitzel3/juju,axw/juju,Altoros/juju-vmware,waigani/juju,bz2/juju,howbazaar/juju,mhilton/juju,frankban/juju-tmp,tych0/juju,bz2/juju,mattyw/juju,fwereade/juju,axw/juju,Altoros/juju-cloudsigma,waigani/juju,anastasiamac/juju,macgreagoir/juju,cmars/juju,sinzui/juju,perrito666/juju,bac/juju,perrito666/juju,cloud-green/juju,kat-co/juju,fwereade/juju,cherylj/juju,frankban/juju-tmp,mjs/juju,gabriel-samfira/juju,thomnico/juju,marcmolla/juju,marcoceppi/juju,wwitzel3/juju,waigani/juju,Altoros/juju-vmware,mikemccracken/juju,makyo/juju,waigani/juju,kat-co/juju,bogdanteleaga/juju,davecheney/juju,ericsnowcurrently/juju,dimitern/juju,howbazaar/juju,marcoceppi/juju,reedobrien/juju,cherylj/juju,mikemccracken/juju,howbazaar/juju,axw/juju,alesstimec/juju,alesstimec/juju,frobware/juju,tsakas/juju,frankban/juju,mjs/juju,anastasiamac/juju,ericsnowcurrently/juju,mjs/juju,mjs/juju,macgreagoir/juju,frobware/juju,davecheney/juju,reedobrien/juju,davecheney/juju,dimitern/juju