API updates

[Steve Poole <sp...@googlemail.com>]

Hi all -  I've just commited some experimental changes to the API.    All
the changes have an  @experimental javadoc tag.

The javadoc is available to view on the Apache hudson server -
http://hudson.zones.apache.org/hudson/view/Kato/job/kato.api-head/javadoc/

Changes are

1 -  All methods that returned an Iterator now return a List
2 -  I've added a new JavaVariable class that is returned from the
JavaStackFrame
3 -  I've added in an ImageFactoryRepository class that uses the
javax.imageio.spi.ServiceRegistry mechanism to discover ImageFactories
implementations

I'm also going to commit a change soon to allow the  ImageFactoryRepository
to respond to a request to return an Image given a java.io.File.  This will
mean adding a method on the ImageFactory interface to allow the ImageFactory
to indicate the file extentions it supports.

These are all experimental changes , along the lines of what we've discussed
before , that are intended to enable real exploration of these ideas.


Cheers

Steve