Added tests for IPv6 to peer grouper tests.
Merge branch 'master' of https://github.com/juju/juju into peergrouper-ipv6-testing
state/api: ApiInfo.Tag now takes a Tag
Merge branch 'master' of https://github.com/juju/juju into peergrouper-ipv6-testing
Some simplification after review.
One final missed change.
Merge pull request #281 from TheMue/peergrouper-ipv6-testing

Added testing for IPv6 to peer grouper tests

So far the peer grouper only tests IPv4. As part of the IPv6 enabling the peer grouper testing now runs all tests for IPv6 too.
Rename config StateInfo() to MongoInfo() to better reflect the purpose of the method
Rename some more stateinfo attrs
Merge pull request #288 from wallyworld/rename-agent-stateinfo

Rename config StateInfo() to MongoInfo()

Agent config's StateInfo() method returns information for how to connect to mongo. There's also State() defined on Environs which returns api connection info. To avoid confusion, prepare for further refactoring, and better reflect the purpose of the method, it was renamed to MongoInfo()
Cleanup imports
Implemented prefer-ipv6 environment setting
Merge pull request #293 from dimitern/prefer-ipv6-environ-config

Implemented prefer-ipv6 environment setting

This is the first of a series of PRs to implement
a "prefer-ipv6" flag across the codebase. As a first
step the following changes were made:
 * Added prefer-ipv6 Boolean flag to the environ config.
   It is optional and defaults to false, and is immutable
   once set.
 * Rather than using a global variable network.PreferIPv6,
   now a new function was implemented: InitializeFromConfig(),
   which takes an interface with PreferIPv6() bool to set
   the (now internal) preferIPv6 flag. This needs to be called
   at start up in several places (bootstrap, MA, UA, CLI), but
   that will happen in follow-ups.
 * Changed the dummy provider a bit to accommodate the changes
   done to the network and config packages.

Next in line will be implementing a PreferIPv6 field in the
agent config, so if it's true we can call InitializeFromConfig
before trying to connect to state or the API to ensure the
user's request to prefer IPv6 addresses / endpoints is honored.
Changed to the well known pattern using collect() für multi-events.
Remove juju.Conn and consolidate some testing code
One comment error.
Merge branch 'master' of https://github.com/juju/juju into flakey-test-machine-interfaces-watcher
Merge pull request #292 from waigani/imports-cleanup

Cleanup imports

Simple PR to cleanup imports.
Extract state/{storage,txn} as top-level projects

juju/juju/state/storage is now juju/blobstore
juju/juju/state/txn is now juju/txn
Code review fixes