new lookups and models

[Moosjes]

Added lookup for postcoderanges
Added lookup by RD
Added lookup by LatLon
Added lookup by exact address
Added models for address and postcoderange

[MaartenScholder]

Thank you for implementing the additional new Api methods.

However, we cannot accept the pull request because the commits are mixed with hundreds of code style changes. At the moment, our code style clearly differs from yours. Without saying which style is better etc., but if we wanted to change it, it should be a separate decision and commits. We cannot just blindly merge any code style, otherwise it might lead to changing from spaces to tabs depending on last author and wind direction. I think an important convention is to respect the style of external code in open source projects.

I really like the api methods, and don't want to sound harsh, but each project has to do some gatekeeping. We probably look into both aspects of this pull request in the near future.