SRFI-151 (bitfiddling) for guile

[Linus Björnstam]

Hi there!

I have "ported" all of srfi-151 to guile. There wasn't that much porting 
involved, since most of the functionality is provided by guile as srfi-60 and 
the basic bitwise arithmetic in guiles standard environment.

It passes all the tests in the srfi document. If one wants to include it in 
guile's main distribution (as FSF-copyrighted LPGL), you would need to make a 
clean-room implementation of the procedures in bitwise-other.scm (bits->vector, 
vector->bits, bit-swap, bitwise-fold, bitwise-for-each, bitwise-unfold and 
make-bitwise-generator). I don't know about the tests, so probably them as 
well. The rest of the code is public domain (code by Olin Shivers edited by 
John Cowan, and code by me).

The repo is here: https://bitbucket.org/bjoli/guile-srfi-151/

and the srfi document can be found here: 
https://srfi.schemers.org/srfi-151/srfi-151.html

Best regards
Linus Björnstam