Include Bazaar digest in legacy charm-info API endpoint.

Also activate the legacy server in charmd.
Move BzrDigestKey from params to lppublish.
Merge pull request #112 from frankban/digest-in-legacy

Include Bazaar digest in legacy charm-info API endpoint.

Also activate the legacy server in charmd.
Merge branch 'v4' of github.com:juju/charmstore into ingest-bundles

Conflicts:
	lppublish/lpad.go