Chal v1.3.0 release

[namanthanki]

Hi all,

I've just tagged v1.3.0 of Chal, a compact UCI engine written in C99.

The headline changes are a full PeSTO/Rofchade tapered eval replacing the old hand-crafted tables, tons of bugfixes and patching around. The engine comes in at 827 lines of code.

Estimated strength is ~2100 Elo, supported by a gauntlet of thousands of games against Stash v12/13/14 and confirmed by SPRT (+224 Elo vs the previous version).

A huge thanks to Pawel Koziol whose mentorship made this release what it is.

If anyone from the CCRL team happens to see this, I'd love to get Chal included in the list so it would be great to have an official rating to track progress across versions.

GitHub: https://github.com/namanthanki/chal