[r=rogpeppe] plugins/juju-backup: tweaks
[r=rogpeppe] plugins/juju-backup: tweaks

This is to address comments I made too late on the
original CL.

I've tried to reduce moving parts where possible
and reduce vulnerability to bash quoting issues.

I changed the indentation from two spaces to tabs,
as I find two spaces hard to see and we use tabs
elsewhere in the code base. I realise that this may
be a religious issue - 4 spaces would also be
a viable option if tabs are not considered OK.

I've left the output pretty much unchanged. Here's
a sample:

% juju-backup
Connecting to machine 0

**************************************************************
Preparing to perform backup
**************************************************************
Older juju backup exists, moving to juju-backup-previous
Removing existing backup archive.....SUCCESS
Archiving backup.....SUCCESS
Making backup directory.....SUCCESS

**************************************************************
Backing up mongo database
**************************************************************
Stopping mongo.....SUCCESS
Backing up mongo.....SUCCESS
Backing up environ config.....SUCCESS
Starting mongo.....SUCCESS

**************************************************************
Copying Juju configuration
**************************************************************
Copying /etc/init/juju-db.conf.....SUCCESS
Copying /etc/init/jujud-machine-0.conf.....SUCCESS
Copying /var/lib/juju/agents/machine-0.....SUCCESS
Copying /var/lib/juju/tools.....SUCCESS
Copying /var/lib/juju/server.pem.....SUCCESS
Copying /home/ubuntu/.ssh/authorized_keys.....SUCCESS
Copying /etc/rsyslog.d/25-juju.conf.....SUCCESS
Copying /var/log/juju/all-machines.log.....SUCCESS
Copying /var/log/juju/machine-0.log.....SUCCESS

**************************************************************
Creating tarball
**************************************************************
Performing tar.....SUCCESS
Changing ownership of backup files to ubuntu.....SUCCESS

Juju backup finished.

Connection to ec2-23-20-40-203.compute-1.amazonaws.com closed.
Copying tarball to /home/rog/src/go/src/launchpad.net/juju-core/cmd/plugins/juju-backup/juju-backup-20131129-1540.tar.gz ...
juju-backup.tar.gz 100% 4650KB 357.7KB/s 00:13
%

https://codereview.appspot.com/34710044/
mikemccracken/juju,cmars/juju,thomnico/juju,mattyw/juju,anastasiamac/juju,ericsnowcurrently/juju,fwereade/juju,frankban/juju,kat-co/juju,mhilton/juju,mikemccracken/juju,voidspace/juju,dimitern/juju,voidspace/juju,dooferlad/juju,bz2/juju,cloud-green/juju,tsakas/juju,bogdanteleaga/juju,mjs/juju,cherylj/juju,mhilton/juju-juju,bz2/juju,alesstimec/juju,waigani/juju,anastasiamac/juju,perrito666/juju,rogpeppe/juju,gabriel-samfira/juju,axw/juju,bogdanteleaga/juju,marcmolla/juju,Altoros/juju-vmware,cherylj/juju,tasdomas/juju,mjs/juju,frankban/juju-tmp,axw/juju,bac/juju,marcmolla/juju,bogdanteleaga/juju,tych0/juju,alesstimec/juju,wwitzel3/juju,waigani/juju,marcoceppi/juju,frankban/juju,frobware/juju,dimitern/juju,cmars/juju,fwereade/juju,marcoceppi/juju,wwitzel3/juju,AdamIsrael/juju,reedobrien/juju,Altoros/juju-cloudsigma,howbazaar/juju,mattyw/juju,sinzui/juju,rogpeppe/juju,tych0/juju,dimitern/juju,frobware/juju,sinzui/juju,tasdomas/juju,alesstimec/juju,gabriel-samfira/juju,Altoros/juju-cloudsigma,dooferlad/juju,perrito666/juju,marcoceppi/juju,marcoceppi/juju,tych0/juju,tsakas/juju,cmars/juju,thomnico/juju,frankban/juju,cloud-green/juju,mjs/juju,howbazaar/juju,frobware/juju,mattyw/juju,anastasiamac/juju,dimitern/juju,bz2/juju,waigani/juju,axw/juju,alesstimec/juju,thomnico/juju,marcmolla/juju,ericsnowcurrently/juju,macgreagoir/juju,reedobrien/juju,mjs/juju,mattyw/juju,gabriel-samfira/juju,cherylj/juju,reedobrien/juju,howbazaar/juju,Altoros/juju-vmware,ericsnowcurrently/juju,tasdomas/juju,dooferlad/juju,voidspace/juju,makyo/juju,macgreagoir/juju,mhilton/juju-juju,bogdanteleaga/juju,mjs/juju,fwereade/juju,tasdomas/juju,perrito666/juju,kat-co/juju,dimitern/juju,davecheney/juju,macgreagoir/juju,davecheney/juju,mjs/juju,makyo/juju,tych0/juju,Altoros/juju-cloudsigma,perrito666/juju,alesstimec/juju,bac/juju,kat-co/juju,Altoros/juju-cloudsigma,cloud-green/juju,kat-co/juju,bz2/juju,mhilton/juju-juju,rogpeppe/juju,axw/juju,AdamIsrael/juju,davecheney/juju,anastasiamac/juju,mikemccracken/juju,howbazaar/juju,bz2/juju,jrwren/juju,mhilton/juju-juju,anastasiamac/juju,makyo/juju,bac/juju,macgreagoir/juju,sinzui/juju,tsakas/juju,makyo/juju,frankban/juju-tmp,dooferlad/juju,cloud-green/juju,frankban/juju-tmp,jrwren/juju,reedobrien/store,kat-co/juju,frankban/juju,mhilton/juju,waigani/juju,Altoros/juju-vmware,bac/juju,davecheney/juju,wwitzel3/juju,howbazaar/juju,marcmolla/juju,voidspace/juju,mjs/juju,AdamIsrael/juju,tsakas/juju,sinzui/juju,wwitzel3/juju,AdamIsrael/juju,ericsnowcurrently/juju,macgreagoir/juju,marcmolla/juju,mhilton/juju,frankban/juju-tmp,reedobrien/juju,perrito666/juju,bac/juju,cmars/juju,cherylj/juju,gabriel-samfira/juju,reedobrien/juju,Altoros/juju-vmware,dooferlad/juju,mikemccracken/juju,frankban/juju,fwereade/juju,mikemccracken/juju,thomnico/juju,ericsnowcurrently/juju,gabriel-samfira/juju,axw/juju,jrwren/juju,mhilton/juju