feat(typeahead): anchor popup left or right of input

[troch]

For issue #1376

[pkozlowski-opensource]

@troch thnx for your PR, I see your use-case. Your proposed fix could be a good one if we would be considering this one directive in isolation. But taking this project as the whole we need this type of functionality in many places (tooltips, popovers, drop-downs etc.). As such we should extract it to a separate service and use throughout the project.

Going to close this one for now, please do open another PR if you are willing to work on the positioning service described above. Thnx for your contribution!