This extracts charencode.c from parsers.c, which seems big enough for me
to hesitate to add new JSON functions. Still charencode.o is linked to
parsers.so to avoid duplication of binary codes.
parsers.c is ~3000 lines and ~2/3 of it is related to the revlog
index type.
We already have separate C source files for directory utilities
and manifest parsing. I think the quite unwieldy revlog/index
parsing code should be self-contained as well.
I performed the extraction as a file copy then removed content
from both sides in order to preserve file history and blame.
As part of this, I also had to move the hexdigit table and
function to a shared header since it is used by both parsers.c
and revlog.c
# no-check-commit
