Added `pick`
Added some of the standard-library style necessities
brought API list up to speed
added some type comments
'cleaning up' tests - for a given definition of cleaner
part way through adding docs - but really must go out -.-
oh, just a little bit more..
Corrected failing tests, and applied benvan's review comments
Merge pull request #1 from hughfdjackson/std-lib-additions

Std lib additions