Check codes returned from the Directions and Map Matching APIs

Fatal Exception: java.lang.NullPointerException: Attempt to invoke interface method 'java.lang.Object java.util.List.get(int)' on a null object reference
at com.mapbox.services.android.navigation.v5.navigation.RouteAnnotationUpdater.update(RouteAnnotationUpdater.java:18)
at com.mapbox.services.android.navigation.v5.navigation.RouteRefreshCallback.onResponse(RouteRefreshCallback.java:33)
at retrofit2.ExecutorCallAdapterFactory$ExecutorCallbackCall$1$1.run(ExecutorCallAdapterFactory.java:70)
at android.os.Handler.handleCallback(Handler.java:761)
at android.os.Handler.dispatchMessage(Handler.java:98)
at android.os.Looper.loop(Looper.java:156)
at android.app.ActivityThread.main(ActivityThread.java:6623)
at java.lang.reflect.Method.invoke(Method.java)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:942)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:832)

I haven't been able to reproduce this. I have this PR but we need to track down the API call that is causing this issue. Wondering if we could send a non-crashing crash report.

Start with the stack trace at RouteAnnotationUpdater.java:18 and RouteRefreshCallback.java:33, then review PR 1916 and the Directions and Map Matching API response handling. Identify which API response or status code leaves the list null, and define completion as preventing the crash while producing a useful crash report.