feature: visual novel engine plugin

[blurymind]

A nice way to stress test the external plugin system is to implement a plugin that adds a visual novel engine that is using inkjs

• possibly use kaboomjs for graphics (using dependency feature of addons) and inkjs for story parsing( since its more mature than bondagejs)
• all wrapper logic should be hosted on a single module js file - hosted somewhere else on github - so it can be used outside of yarn editor
• adds a playtest button and possibly even a single html file export button (with all resources baked in it as base64?)
• addon file hosted on gist should also be easily bundled by including in the public folder