Allow setting the deploymentKey on Android (#1115)

Author: christophermark

android/app/src/main/java/com/microsoft/codepush/react/CodePush.java

@@ -319,6 +319,10 @@ public static boolean isUsingTestConfiguration() {
         return sTestConfigurationFlag;
     }
 
+    public void setDeploymentKey(String deploymentKey) {
+        mDeploymentKey = deploymentKey;
+    }
+
     public static void setUsingTestConfiguration(boolean shouldUseTestConfiguration) {
         sTestConfigurationFlag = shouldUseTestConfiguration;
     }