Update README.md
Remove old .xcworkspace.
First SMS auth flow screen.

Added 'SMS' subspec.
Disable user interaction when transitioning.
Use size classes SB for example.
Modal presentation style in iPad.
Enter code screen.
Hide keyboard on tap.
Custom view for phone input.
Show SMS auth embedded in Nav controller.

Created VC to pick country code.
Display countries with their dial codes.
Search for country.
Return selected country.

Localized texts in Dial code VC.
Handle selected country.
Set default country to US.
Handle country names with NSLocale.
Created operation to fetch access token.
A0APIClient expose clientId, tenant and BaseURL.

Use operation to fetch access token in SMS send code screen.
Use block to fetch client secret.
Operation to send SMS codes to a phone #.