List more kinds of possible packages/documents/aliases in zsh completion

[mgkurtz]

Thanks a lot for providing a zsh completion ❤️ I love shell completions and so I improved it (at least from my point of view) a little further by enlarging the list of package and document names, the completion script suggests.

The current completion uses the package names from $TEXMFROOT/texlive.tlpdb, this is usually nice, but with TeX-Live installed as Debian package, this texlive.tlpdb does not even exist 😕 Hence, I added five more sources of which at least some should exist and provide helpful completions:

• Package names listed in a local $TEXMFHOME/texlive.tlpdb.
• If texlive.tlpdb exists neither locally, nor system wide: fallback to texdoc’s own Data.tlpdb.lua.
• PDF files listed in the ls-R file.
• Aliases registered in texdoc-dist.cnf and texdoc.cnf.
• Any files found in $TEXMFHOME/doc.

I hope you like it and feel free to criticize 😀

[wtsnjp]

Thanks for the suggestion! Looks good to me.

@Freed-Wu if you have time, could you please look at the changes in the zsh completion function and share your thoughts with us?

[Freed-Wu]

• above: PR
• below: original

LGTM