Add identity and identityof functions.
Range fetching of S3 data (byte ranges) and fetching to memory.
Better naming conventions for enumeratees.  xxx-map, xxx-flapmap, ...
Split and build URI paths.
S3 specific URI paths.
prelude.rkt for mapred library.  DynFn macros.
Attempt to dynamically load configuration which is a standard Racket module.