Remove juju.Conn and consolidate some testing code
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
Fix import ordering
Merge pull request #296 from axw/extract-state_storage_txn

Extract state/{storage,txn} as top-level projects

juju/juju/state/storage is now juju/blobstore
juju/juju/state/txn is now juju/txn
Fix NetworkInterfaceSuite.TestRemove random failure
Missed an import, or merged badly, or ...
Merge upstream
Merge pull request #297 from axw/state-remove-state-txn-again

Missed an import, or merged badly, or ...
Merge branch 'master' of https://github.com/juju/juju into remove-juju-conn
Fix bad merge
Merge pull request #298 from bz2/network_interface_random_test_failure

Fix NetworkInterfaceSuite.TestRemove random failure

The NetworkInterface type must be serialised as %#v not %v for errors.NotFoundf so the GoString method gets used. Also improve the test error match to ensure the correct serialisation is used. Without this change, the test could randomly fail if the bson id happened to contain an 0x0A byte, as `.*` does not match newlines.
Merge pull request #295 from wallyworld/remove-juju-conn

Remove juju.Conn and consolidate some testing code

Part of the journey to cleaning up state and environ dependencies.

juju.Conn is no longer used. juju/conn.go and juju/conn_test.go are deleted. Some remaining functionality from conn is moved to juju/testing/conn.go, and also apiconn_test.go. Of the code moved to testing/conn.go, there is still potentially unneeded conn functionality - this will be removed next.

Test suites which used to have a State and an Environ and a Conn now only have a State and an Environ.
conn_test.go included tests for DeployService, so these tests were moved to deploy_test.go where they belong. 

Tested live on ec2 - deployed a unit, ensured ha.