Customizing the Services Menu Processor
---------------------------------------

The services menu bundle has no built-in knowledge of News or Alexandra.
It is easy to modify it to invoke other external applications. Two things
are necessary for OmniWeb to invoke an external application for a
particular URL:

   1. The ServicesMenuProcessor must be registered as being able to
      interpret that kind of URL.

   2. There must be a default indicating the Services Menu item to
      invoke.

Part 1 is handled by the "converts" list in the Omni.dictionary. The processor
should specify an "input" type of "url/scheme", where scheme is the 
relevant URL scheme, and an "output" type of "omni/source".

Part 2 is handled by the "defaultsDictionary". For URLs, the processor looks
for a default named "URLServices". The keys of this dictionary are URL schemes
with colons appended (e.g. "news:"); the values are strings corresponding
to Services menu items;

For non-URL content, the processor looks in a default named "MIMEServices";
the keys here are MIME types, the values are services menu names as before.

For examples, see the dictionary in this bundle.

Notes:
  - The data returned from the service, if any, is discarded.
  - Even if a default value is specified in the defaults database,
    it must be mentioned in the bundle's defaultsDictionary for OmniWeb's
    defaults machinery to read it.

