Bug/permission check

[evan-masseau]

Please take a moment to fill out the following:

Fixes #329 and #328

Changes Proposed in this pull request:

• Default on iOS to just checking WhenInUse permission
• Allow the programmer to override that check to require Always permission
• Programmer can also request Always permission of the user separately, which is closer to apple's more recent guidelines about requesting In Use and Always permission in separate stages. https://developer.apple.com/documentation/corelocation/choosing_the_location_services_authorization_to_request