State upgrade step: add env UUID to openPorts collection

Add an upgrade step targeting 1.22-alpha for the openPorts collection. Append the State Environment UUID to the document _id field. Add the following fields to the document: "env-uuid", "machine-id","network-name".

Refactor state/ports.go to use the new fields. Refactor mgo queries to included the environment UUID. Refactor state/upgrades.go helper function addEnvUUIDToEntityCollection to support collection specific upgrades by using variadic option functions. Skip failing upgrade tests which do not target current version.
Merge branch 'master' of https://github.com/juju/juju into migrate-openPorts

Conflicts:
	state/upgrades.go
Merge branch 'master' of https://github.com/juju/juju into migrate-openPorts

Conflicts:
	state/upgrades_test.go
	upgrades/steps122.go
	upgrades/steps122_test.go
move context inside runner -- integration tests still passing, nothing else even checked
fix context package tests
fix uniter/operation tests
State: add EnvUUID to statusDoc

Add State's environment UUID to the EnvUUID field of a statusDoc on creation.
rename uniter/context to uniter/runner
Merge branch 'master' into uniter-deemphasise-context
Merge branch 'master' of https://github.com/juju/juju into migrate-openPorts
Merge branch 'master' of https://github.com/juju/juju into migrate-openPorts
Merge branch 'master' of https://github.com/juju/juju into migrate-openPorts
Add missing meterStatus upgrade step.
Merge branch 'master' of https://github.com/juju/juju into migrate-openPorts
Merge pull request #1231 from fwereade/uniter-deemphasise-context

uniter/context: move context inside runner


   * Renamed uniter/context to uniter/runner
   * runner.Factory now creates runner.Runners (rather than context.Factory creating context.Contexts)
   * loads of consequent test changes
   * loads of tedious renames


(Review request: http://reviews.vapour.ws/r/541/)
Merge branch 'master' of https://github.com/juju/juju into migrate-openPorts
Merge pull request #1233 from waigani/set-env-uuid-on-docs

State: add EnvUUID to statusDoc

Add State's environment UUID to the EnvUUID field of a statusDoc on creation.

(Review request: http://reviews.vapour.ws/r/543/)
Merge pull request #1186 from waigani/migrate-openPorts

State upgrade step: add env UUID to openPorts collection

Add an upgrade step targeting 1.22-alpha for the openPorts collection. Append the State Environment UUID to the document _id field. Add the following fields to the document: "env-uuid", "machine-id","network-name".

Refactor state/ports.go to use the new fields. Refactor mgo queries to included the environment UUID. Refactor state/upgrades.go helper function addEnvUUIDToEntityCollection to support collection specific upgrades by using variadic option functions. Skip failing upgrade tests which do not target current version.

(Review request: http://reviews.vapour.ws/r/496/)