Fixes #504 Configuration dialog for the Shelve command
Was already merged in Bitbucket before import, marked as merged by the import user
- Starting 'issue504-config-dialog-for-shelve-command' branch.
- Updated maintenance notes to describe the relations between handlers, jobs, operations, dialogs, command clients.
- Updated maintenance notes with information about creating dialogs.
- Added a configuration dialog for the shelve command.
- Changed definition of ShelveHandler so that its definition is consistent with its parent class.
- Added a preference page for Shelve.
- Configured the full chain (from handler to command) to support the Shelve configuration bean and added support for include and exclude name patterns.
- Refactoring: moved some classes to existing packages.
- Refactoring: renamed MercurialPreferenceConstants to PreferenceConstants.