Getting ready for release 2

Clean up tests
simplify cap and recap semantics
add cap/recap example to syntax.clj
Fix two bugs and clean up subex modeling

Fixed the bug where verdicts were not considered during branch
folding.

Fixed the bug where exec returned Passing/Failing instead of
Passed/Failed.

Cleaned up the way subex returns captured values from the sub-model.

Updated trees example to use latest API.
Add path record

Eventually, I'll use the record instead of the rather unwieldy path
vector throughout the Serial logic.
slight renaming for :bnf values
ord -> cat

This fits better with regular expression terminology.
qty -> rep

again, fits better with regex terminology.
Version 2.0