Reworked Autocomplete, fixed dropdown issues

[vitalif]

Hi!

Thanks for your library, I like it very much. However it has several issues with autocomplete. Most (I hope all) of them is fixed in my version. Features:

• Clearable dropdown & autocomplete
• Autocomplete rendering in Portal
• Simplified Autocomplete code
• Fixed onFocus/onBlur issues with dropdowns
• Always controlled Inputs

Basically I think I've done at least some part of #1169

I may split out autocomplete and other fixes in separate commits/PRs if you want. Also it's probably missing docs. But first I want to submit the pull request so you can check it out...:)