Benchmark check-in for HTMLParser; created unit test and start sketching out implementation (state machine).
Add test runner script
Benchmark check-in; more WIP for HTMLParser
First working version of HTML table parser (unit test passes).  Still want to do some refactoring.
Sort out error handling for basic examples of badly-formed HTML, including unit tests.
Move functionality shared by states for header cells and data cells into an abstract base class.
Clean-up for HTML table parser - add docstrings, tidy up formatting