Gamepad and Keyboard get_value autocomplete doesn't work because ace
fills in the matching parenthesis -- typing 'Gamepad.get_value(' writes
'Gamepad.get_value()'. So try to add a way for makeContextCompleter to
require a caret position, like inside the parens. Very broken right now
and I'm not sure why.

Add addEditorTooltips skeleton.
Don't use alias for TokenIterator in addEditorAutocomplete.

Uninstall redux because it was causing problems for the clean install on
Clorox.

Try to fix bad completions for Gamepad/Keyboard.get_value by slicing
away already-typed part. Observations:
  Completion is multiple tokens (e.g. when quoted):
    slice is needed to remove already-typed string from completion.
  Completion is single token:
    unsliced is needed or else existing text is replaced with sliced
    completion, effectively deleting the already-typed bit.
Revert to using unsliced completions, as Ace can't seem to decide
between replacing partially typed completions or appending to them, and
I don't know how to programmatically predict which Ace will do.

Completion slicing still doesn't work, so Gamepad/Keyboard.get_value
looks silly when quotes are already typed.

Add Robot.get_value doc as proof of concept. Text was pulled from api.md
in the runtime repo. Styling still needed.
Add HighlightedCode which wraps an AceEditor with appropriate
configuration to be a highlighted read-only code block.

The doc stuff will eventually have to live in its own directory
somewhere if it's going to be reused. The API help window could probably
just sort apiHelpComponents by key and concat them.