Use Crashlytics to track Crashlytics initialization

init.java

long start = System.currentTimeMillis();

boolean isDebugApplication = ...
Fabric.with(context, new Crashlytics.Builder()
        .core(new CrashlyticsCore.Builder().disabled(isDebugApplication).build())
        .build());

long initDuration = System.currentTimeMillis() - start;
Answers.getInstance().logContentView(new ContentViewEvent()
        .putContentName("Fabric initialization time in milliseconds")
        .putCustomAttribute("time", initDuration));