Use kotlin extension functions to expose APIs on mapboxMap

[tobrun]

Kotlin extension functions allow to expose APIs on existing classes. The idea is to expose APIs of plugins directly on MapboxMap to create a real plugin system. This would allow for the following developer experience:

• add maps gradle dep
• add plugin 1 gradle dep
• add plugin 2 gradle dep
• integrate maps with all public api found on MapboxMap

cc @cammace @zugaldia

[cammace]

Watching the talk at Google IO about ktx, there might be another option which would remove the need to publish a second artifact for each plugin to support this functionality. See proposal KEEP-110 which adds annotations which you can easily slip into your existing library to make the APIs more friendly. Not sure if we want to hold out for this proposal to add ktx support but it is an option.

[tobrun]

Some movement on Maps KTX is moving in #712 and #715

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

This issue has been automatically detected as stale because it has not had recent activity and will be archived. Thank you for your contributions.