Fix srcdir for the jrcs build target.

Since the old srcdir was a parent of the actual source root, Ant got
confused and always rebuilt jrcs, also in incremental builds when
jrcs hadn't been changed. Now, incremental builds will only rebuild
it if something has changed in the jrcs code.
fixes for FilePath searches being broken (in QueryBuilder),
cleanups, path tokenizer fixes and tests
fixes issue #9