SourceOpener gives poor display on multiple file path hits

[jennybrown8]

When opening a core wicket class, like DefaultDataTable, the SourceOpener disambiguation dialog is not correctly displaying the paths of the files it thinks it found. Also, clicking on one results in a file system exception, "Path must include project and resource name: /myproject"

Prior to fixing issue #4 this seemed to be working, so I presume it's a side effect bug I didn't discover while testing #4. Presumably it's matching against the wicket-core jar in the maven dependencies container in each of those projects.

Need to figure out exactly where the matching weirdness and display weirdness are sneaking in, and fix both locations.