Document how to avoid non-free dependencies on Android (#313)

* Document how to avoid non-free dependencies on Android

* Replace explicit version number with placeholder

README.md

@@ -57,13 +57,20 @@ The iOS API documentation is available at https://maplibre.org/maplibre-gl-nativ
     ```gradle
         dependencies {
             ...
-            implementation 'org.maplibre.gl:android-sdk:9.4.0'
+            implementation 'org.maplibre.gl:android-sdk:<version>'
             ...
         }
     ```
 
 3. Sync gradle and rebuild your app
 
+*Note: MapLibre by default ships with the proprietary Google Play Location Services. If you want to avoid pulling proprietary dependencies into your project, you can exclude Google Play Location Services as follows:*
+```gradle
+    implementation ('org.maplibre.gl:android-sdk:<version>') {
+        exclude group: 'com.google.android.gms'
+    }
+```
+
 ### iOS
 
 1. To add a package dependency to your Xcode project, select File > Swift Packages > Add Package Dependency and enter its repository URL. You can also navigate to your target’s General pane, and in the “Frameworks, Libraries, and Embedded Content” section, click the + button, select Add Other, and choose Add Package Dependency.