nickle: update to 2.92.

Version 2.92
debian: Build depend on a couple of packages
Use CC_BUILD to generate math test tables
Add ctype.h, remove explicit lex func prototypes from lex.l
Remove 'const' attribute when assigning to tm_zone field
Allow use of libedit in place of readline
Check for all readline helper functions separately
Define _GNU_SOURCE in edit.c to get asprintf declared
Remove redundant box value check in ThreadBoxSetDefault
test: Allow "UTC", "GMT", or "NONE" to be returned for GMT time zone
Make tm_zone and tm_gmtoff fields optional
Autodetect 'significand' function
Use base-10 for all float exponents. Use base 2 for base 2/8/16 powers
Support C-like hex float values in lexer
Add ChaCha implementation

(wiz)