Upgraded version of elm-hot

[realistschuckle]

It seems that the original elm-hot package may now be unmaintained.

I would like to propose a new package to be included with parcel: @curtissimo/elm-hot. In contrast to the original elm-hot, this one has:

• Support for Worker-scoped HMR (new feature)
• Support for "headless" Elm applications (to address Allow to init a worker (not bound to a DOM node) klazuka/elm-hot#75)
• style-src 'self'-compliant execution for content security policies (to address Can't use Elm asset when there is a Content Security Policy #5351)
• The most recent dependencies
• Working integration tests

I've created a PR for this: #10256.