Add lua modules for plugin support out of the box

[fzipi]

Our official plugins use the following lua modules (from this query):

• socket
• zlib

so we must add those to the official image.

Packages are:

• lua-lzlib
• lua-socket

[fzipi]

I've added a comment, but didn't followed up this one for openresty. What do you think @matias-at-skribble @TafkaMax? What is the best option here? Using luarocks or adding them as base packages?

[fzipi]

No comments, so I'm dropping this. 🤷