Typeahead - do not preselect first match

[xelibrion]

This pull request addresses issue #908

[mrzepinski]

+1

[xelibrion]

Clarification - this pull request implements functionality with a contract proposed by @pkozlowski-opensource here

[davelosert]

+1

[pkozlowski-opensource]

@xelibrion could you please squash commits and remove commits that are not essential to adding the required functionality (you can send those are as a separate pull requests).

Small, focused PRs are much easier to review and got much more chance of getting merged fast.

[xelibrion]

@pkozlowski-opensource done

[pkozlowski-opensource]

@xelibrion this starts to look good, thnx. I've left one comment (other one is to be ignored). I need to have another look at the code / tests but it should land soon.

One more thing I was wondering about, from the functional point of view: all the implementations I've checked (typeahead.js, angular-ui autocomplete) will go through the "unselected" state when you use up/down arrows. I'm not sure if this matters, though. WDYT?

[xelibrion]

@pkozlowski-opensource not sure that I get you're saying about "unselected" state. Is it related to their onSelectCallback implementation?

I fixed indentation in a couple of places, please let me know if you're happy with the diff, I'll squash these commits in one - I didn't want to overwrite first commit for now as there are a few comments on that one.

[wesleycho]

Can you update this PR based on current master?

[chrisirhc]

Closing as this was addressed via #2916 . Thanks for your work though.