V0.4.0 adds specs to characterize and test advising Java classes when running on JRuby and adds several
API enhancements.

Bug fixes:
17844 JRuby - Advising types, Aquarium thinks the type is a string
17883 Workaround for JRUBY-2089
18090 JoinPoint#invoke_original_join_point only works with :around advice

Enhancements:
17834 Allow :class and :module (and variants) wherever :type is allowed
17881 Add specs that exercise advising Java types and objects using JRuby

#17844 occurred because of the way JRuby encodes Java packages into modules. Aquarium now properly handles
JRuby types.

#17883 reflected a JRuby bug, so a workaround was required.

#17834 allows the user to substitute the words "class", "classes", "module" or "modules" anywhere the words
"type" and "types" are used in the API, since some users might naturally want to write aspects like this:

around :calls_to => :my_method, :in_class => MyClass do ...; end

However, there is no enforcement to ensure that "class" is only used for classes and "module" is only used
for modules, etc. Note: it's possible we'll enforce this in some future release, as a way of saying things
like "only advise classes that match ...", etc. Caveat Emptor!

For #18090, a bug prevented JoinPoint#invoke_original_join_point (which allows you to bypass all advices at
the join point) from working except for :around advice (and yes, the specs didn't cover this adequately -
gasp!). Now fixed.

For #17881, I created a separate set of specs for JRuby, so it's easier to run the "regular" Aquarium
specs using MRI and the JRuby-specific specs separately with JRuby. The new "jruby" directory contains a
Rakefile, another set of specs, and Java example code for the specs to use. The default Rakefile task
re-runs the main Aquarium spec suite using JRuby, to confirm that the suite passes successfully, then it
runs a set of different specs that load sample Java interfaces and classes into JRuby and then advises
them with Aquarium.

I found a few JRuby bugs and other behavior differences between MRI during this release. I was able to handle
them with modifications to the Aquarium code. If you "grep" the Aquarium "lib" and "spec" directories for the
word "jruby" (ignoring case), you'll find notes about these issues and the workarounds I implemented.

The separate JRuby spec suite shows what you can and cannot do with Java types. As a side benefit, it also
demonstrates how Java types, objects, and methods are mapped to Ruby. There are some important limitations,
however. See the jruby.html page on the website or the README for more details.

Note: JRuby 1.1RC2 was used.