V0.6 of exyus available - including DB support

[mca]

i finally got around to packaging up the db support for exyus. turns
out it has been four weeks since the last release - wow.

i also incremented the version from 0.05 to 0.06 since the database
support is a major change. i built a couple of sample db-based apps as
part of testing. the strongest one right now is the User Group Members
example. this one is interesting because it offers a way to handle
DELETE and PUT via FORM POST. even though DELETE and PUT were in the
HTTP web spec early on, it remains unsupported by the common browsers.
my solution is to overload the document id that is the target of the
POST. for example:

-- standard HTTP methods
POST /resource/ (creates a new document)
GET /resource/1 (gets an existing document)
PUT /resource/1 (updates an existing document)
DELETE /resource/1 (deletes an existing document)

-- handling PUT and DELETE via FORM POST
POST /resource/1;update (updates an existing document)
POST /resource/1;delete (deletes an existing document)

the last two examples show the overloaded document id in action. on
the server tehre is a URI roule that accepts the /resource/{id};update
pattern and then executes the PUT or DELETE as expected. this makes
sure the actual PUT/DELETE are logged in the server logs and reduces
the amount of special coding needed to support POSTed PUT/DELETE. it
also makes sure that any cache invalidation rules you have for PUT or
DELETE will be properly honored.

anyway, lots of other cool stuff are in this update. i'll post about
them over the next few days.