Gut the backup plugin, but keep it around for backward-compatibility.
Use the old plugin code for 1.20.
Add a deprecation warning message.
Add a TODO comment about removing the plugin.
Improve the visibility of the divider comment.
Skip new backups for 1.21 as well.
Add upgrade step to put the system identity back.

Conflicts:
	upgrades/upgrade_test.go
missing import.
state: cleaner env config generation in EnvironSuite

A small cleanup made after discovering testing.CustomEnvironConfig().
all: move MachineJob decl to state/multiwatcher
tests pass
cleanups
Updated dependencies.tsv for juju/utils
Setting default network bridge name on config creation.
Merge pull request #1195 from dimitern/update-dependencies-juju-utils

Updated dependencies.tsv for juju/utils

This is needed to apply the fix for http://pad.lv/1394524
which landed on juju/utils, but juju-core is not yet using it.

(Review request: http://reviews.vapour.ws/r/506/)
Actions :: Consolidate and cleanup Collections

 - Consolidate action collections into one actionDoc collection.
 - Add actionNotificationDoc collection to split notifications of newly
   enqueued Actions from notifications of changes to the Actions.
 - Add new StringsWatcher: actionStatusWatcher for watching actions that
   are in a specific state.
 - Move state Action specific code all into the action.go file.
 - Move interface definitions into interface.go.
 - Refactor ActionReceiver calls to keep db access all in the core
   action.go file.  Also use names.Tag in more places.
Fixes per review feedback
Fix for feedback from review
More review feedback
Couple more naming suggestions