Function: bittest
Section: conversions
C-Name: gbittest
Prototype: GG
Help: bittest(x,n): gives bit number n (coefficient of 2^n) of the integer x.
 Negative numbers behave as if modulo big power of 2
Description: 
 (small, small):bool:parens     ($(1)>>$(2))&1
 (int, small):bool              bittest($1, $2)
 (gen, gen):gen                 gbittest($1, $2)

