ActionRequested hook rename to Action

ActionRequested was also removed from UnitHooks.
ActionRequested hook rename to Action

ActionRequested re-added for charm v4 compatibility.
Merge pull request #53 from binary132/actionhook-rename

ActionRequested hook deprecated and renamed to Action
migratebundle: new package

This is the start of the code to migrate old-style
bundles to new-style bundles.
migratebundle: fix comment
migratebundle: rename oldBundle to legacyBundle
migratebundle: use Replacer instead of Map in test code
Merge pull request #54 from rogpeppe/019-migratebundle

migratebundle: new package