PR: dust documentation

[alekcz]

Added doc command to dust

dust doc has two useages:

• Usage 1 only searches the namespaces loaded into dust: stdlib, io, fs, io
• Usage 2 searches loads and searches all namespaces (namespaces have to be added manually to source at the moment). All occurrences of the function are shown except if the function is present in stdlib.

Usage 1: dust doc

$dust doc chan

chan

     Function not found. Broaden search using -all flag.

$

Usage 2: dust doc -all

$dust doc chan -all

pixie.channels/chan

    Creates a CSP channel with the given buffer. If an integer is provided as the argument
   creates a channel with a fixed buffer of that size. 

  pixie.csp/chan

    Creates a CSP channel with the given buffer. If an integer is provided as the argument
   creates a channel with a fixed buffer of that size. 

$

[heyLu]

Thanks for this, I have a couple small comments, which you'll find inline.

[heyLu]

Thanks a lot! :sparkles: