Add target species and monitoring areas dynamically

[rbergm]

Problem summary

The definition of monitoring areas and target species are currently loaded into the app as assets and therefore need to be present when the APK is created. This also means that in order to adapt the App to a different conservation area it needs to be recompiled and installed as a completely different app. This approach is not practical for a real public usage.

Suggested solution

Add a settings view which enables the user to load new target species and monitoring areas (and maybe even offline maps). The user should also be able to select which natural reserve to use.