add provides to env.rkt
more functionality in pcomb.rkt
work on new draft of parser
simplify env.rkt, no more macro-generating macros
refactor env.rkt a bit
env.rkt: bugfix
simplify env.rkt a little
values.rkt: add more maybe functionality
oops, fix @infix-parser in env.rkt
document @infix-parser better
more work on rewrite of parser
holy shit it parses things now