Orphan classes in java-support

[Rod Widdowson]

I started looking at the HttpResource this morning and realized that it was
the only code which made any use of a whole slew of classes in java-support.

This spurred me to pick up an old AI of mine
https://issues.shibboleth.net/jira/browse/JSPT-37 which was to check how
many of these classes are being used. 

I found it quite educational to do this, and I have just annotated that case
with a list of orphans, plus some 'single use' classes.  Note that I did
this mostly by using eclipse, and so some of these classes may well be being
injected via Spring.

I do not have the visibility into huge portions of the code, so I have no
way to know whether these orphans or nearly orphans are expected to be as
such, whether they have a future use or whether there is code in other
facilities which is duplicating this.  

I'm certain that some of these have to stay (@Negative makes sense if you
have an @Positive), but I also suspect that :

 - Some should be being used in more places than they currently are.
 - And that some should be removed.

Can people take a pass over the list (which I have just reformatted to make
it easier to read) and comment?  

Thanks

/R