feat(typeahead): add 'show-hint' option

[chenyuzhcy]

This is related to #2570

Add a read-only input that has the same postion as the original input

[Foxandxss]

I must say that I absolutely love your work. I wish all the PRs would be like this one and the others you made.

As a suggestion that would help us immensely is to create a plunker with your solution working. You can open the current typeahead demo on plunker, create a new file and paste the tpls bundle that contains your patch (as simple as grunt after-test to generate it).

Thank you again.

[chenyuzhcy]

Thanks for your compliment!
This is a plunker for this pr: http://plnkr.co/edit/5oWIfw4z14uOVo6KzPu7?p=preview
I'll try to do this in the future too. Glad I can help!

[wesleycho]

Seconded on the admiration of the great work - these are some high quality PRs you have put together, and I greatly appreciate the effort put into them. It is rare that we see work this good come out of the blue.