Adding support for the CGI-based editor:

Adding support for the CGI-based editor:
- Exported get_actions()
- Added new function free_alias_list()
- Added support for {{settings}} and {{description}} blocks
  in the actions file.  They are currently ignored.
- Added restriction to only one {{alias}} block which must appear
  first in the file, to simplify the editor's rewriting rules.
- Note that load_actions_file() is no longer used by the CGI-based
  editor, but some of the other routines in this file are.