Improve support for Andrioid M

Checks for and requests runtime location permissions (fixes #2110)
Improved the styling of the location FAB
Removed redudant drawables
Fixed various Java and Android warnings and deprecated functions
A few other tweaks

android/java/MapboxGLAndroidSDKTestApp/src/main/res/values/styles.xml

@@ -7,7 +7,6 @@
         <item name="colorPrimary">@color/primary</item>
         <item name="colorPrimaryDark">@color/primaryDark</item>
         <item name="colorAccent">@color/accent</item>
-        <item name="android:windowBackground">@color/white</item>
     </style>
 
 </resources>