Shorter names for the webservices

The "action" filed in the moodle log table is limited to 40
chars. That is why the webservice names have been changed.
Recent Activities list implemented

Recent Activities list has been added.
- The Recent Activities list is accessible from the toolbar.
- A badge on the RA toolbar button indicates the number of
  the recent activities.
- Clicking on the RA toolbar button shows the RA list.
- Clicking on entries of the RA list shows the corrispondent
  module.

This commit carries a lot of new modifications.

- Changed the webservice names, shorter version
- Renamed Page store to Pages, for consistency
- Use the componentQuery in the pop function (Home button)
- User names in the post are now processed by
  the DataItem:updateRecord function. This way the names
  are rendered when necessary.