Support all DOM events

[shamrin]

• [x] subscribe to events by [… on: "mouseenter"]
• [x] change [#html/event/…] to [#dom/event, event: …]
• [x] add events.ts example
• [ ] remove listeners when removing on attribute
• [ ] change old [#html/event/click] to [#dom/event, event: "click"]
• [ ] get access to <input> value (likely in a separate PR)
• [ ] event.remove("tag") → event.remove() once PR #797 is part of refactor-runtime branch

PR is not finished because I'm not sure about [#dom/event, event: "click"] part and about the explicit subscription. Comments?

[cmontella]

We have to sort of come up with a convention here. In the eve syntax, we have

search @event
  [#click]

Which would make sense to become [#dom/event/click]

I think we should resist the temptation to be too highly specific with tags though, keeping them shallow and getting more specific with attributes. "dom/event" is probably specific enough a tag, so I agree with the change you've made.

[shamrin]

Sorry for late reply! I'm closing this, because the issue was fixed by PR #823 and other changes.