Plan for integrating the next-generation parser

[Jono]

After talking to Mitcho on the phone, I wrote this list of tasks that we need to do in order to integrate the next-generation parser into the main code trunk.

0. put mitcho's new parser code in repository
1. Design new query-based public API for parser.  Put a thin wrapper around the current parser to obey the new interface.
2. alter makeParserForLanguage to instantiate either old or new parser, depending on a parameter passed in.
3. Make new parser implement the new query-based API.
4. move parser unit tests out to separate file; update unit tests to fit new expected parser behavior and new API
5. Continue making improvements to new parser, until we are ready to make it the default and phase out the old one.

--Jono