basic tracking works
skip unexpected json in tracking, handle primary and secondary keys
send metadata in track() by default to pair nicely with parse()
document track()
0.10.0
emit the meta event from the parser
0.11.0
augment the parsed stream with {start,end}Keys
emit augment event for augmented streams
track() using key maps for client-provided arrays
0.12.0
use a pre hook instead of a post hook for put atomicity
0.12.1
thread the limit parameter and let augmented functions have opts
0.13.0