Equality Problems with ActiveResource::Base

The == method was improperly implemented. Therefore, the test provided in the patch would fail. Essentially, two resources with different prefix options passed the equality check. I don't think the .equal? should have been used in the object equality comparison implementation (== method), as per the RDoc for Object "it is used to determine object identity (that is, a.equal?(b) iff a is the same object as b)". For now, I think comparing, at minimum, the id and prefix_options fields is appropriate.