TEXMAP addition to Official Library Spec

[Eugen]

I proposed the following addition to the Official Library Spec to go with the proposed rev the !TEXMAP meta:

Under META Commands add:

!TEXMAP Meta
The !TEXMAP NEXT command or geometry2 lines (as outlined in the Texture Mapping (!TEXMAP) Language Extension) will not be used.

"Texture Mapping (!TEXMAP) Language Extension" (https://www.ldraw.org/spec/texmap.html) link not exists or moved.

Actual correct link: https://www.ldraw.org/texmap-spec.html

And the same page has one more link: https://www.ldraw.org/documentation/ldra...pping.html