Address look up tool for webforms

Feature Request Summary: 

Zendesk Support should have the ability to allow customers to search and add their postal address on web forms. In the UK this could link to the Royal Mail API or flat file data.

Description/Use Cases: 

Customer could complete a web form and confirm various identity checks by entering name, DOB, and postal address, with the latter postal address populated from the linked address search tool rather than freeform input (and potentially erroneous associated manual inputs e.g. spelling).

Business impact of limitation or missing feature:

This is important for our business as our agents are unable to achieve first time resolution on some scenarios, as customers don't provide their address, thus the agent needs to reply requesting this information to pass identity checks.