Properly suppress keys and notifications in all modes

Properly suppress keys and notifications in all modes

- Many modes previously forgot to suppress when getting a partial match
  for a command.

- Caret mode no correctly suppresses when entering a count.

- Ignore mode and Hints mode now explicitly make sure that notifications
  for counts are not shown in their `onInput` methods.

- The keys you've entered so far when filtering hint markers by element
  text now properly re-appear after the keys of a partial command match
  have been cleared due to the `timeout` option.

- `EnteredKeysManager` has been removed from events.coffee and has been
  merged into `Vim`, which turned out to be a nice refactor.