Add build tools

[timotheeg]

Probably should look at vite or parcel to build, deploy install NTC.

Stuff that should be buildable:

• several assets are loaded from the local directory /vendor. All assets therein should come from easily updatable versions (as opposed to the one-off download I have done -_-)
• peerjs connection params are hardcoded
• js assets are nor minimized
• all assets path are absolute