Rename the rest of the internal events to the onDid* pattern

It's super weird in the docs to have the events mixed in with the other methods. If there is a class method, the docs will show:

```
## Methods

.someClassMethod()
.someOtherClassMethod()
::onDidSomething(callback)
::onDidSomethingElse(callback)
::someInstanceMethod(callback)
::someOtherInstanceMethod(callback)
```

I want it to be clear that the event methods are events. IMO, every event should be under an `Event Subscription` heading.