Backport: Updating goyaml and goamz versions to latest.

Conflicts:
	agent/format-1.16.go
	agent/format-1.18.go
	cmd/juju/get_test.go
	cmd/juju/status_test.go
	container/lxc/lxc_test.go
	dependencies.tsv
	environs/configstore/disk.go
	juju/testing/conn.go
	provider/common/state.go
	provider/common/state_test.go
	worker/uniter/uniter_test.go
Merge pull request #522 from katco-/v1.20-backport

Backport: Updating goyaml and goamz versions to latest.

Conflicts:
	agent/format-1.16.go
	agent/format-1.18.go
	cmd/juju/get_test.go
	cmd/juju/status_test.go
	container/lxc/lxc_test.go
	dependencies.tsv
	environs/configstore/disk.go
	juju/testing/conn.go
	provider/common/state.go
	provider/common/state_test.go
	worker/uniter/uniter_test.go