Component `fallback` and `disconnect` VDOM

[Archmonger]

trafficstars

Current Situation

There currently is no convenient way of reacting to WS disconnection within components without doing so in the JavaScript websocket.onclose event.

Proposed Changes

Allow all components to have a

• fallback=...
  • Pre-generated HTML when the initial render (client's first WS connection) couldn't occur
  • Probably only feasible to exist on a top level component
    • ex. @component(fallback=...)
  • Probably will be reliant on template tags
    • Maybe this fallback HTML is serialized as a string?
• disconnect=...
  • Pre-generated HTML displayed in the event of a websocket disconnect

Implementation Details

See here for more details.

[Archmonger]

I've expanded the concept of this one to fallback and disconnect as separate entities for flexibility.

[Archmonger]

Closing this in favor of #653