moved android implementation from /app to /android, rnpm link did not find the android implementation from app -directory.

android/src/main/java/com/bitgo/randombytes/RandomBytesModule.java

@@ -0,0 +1,31 @@
+package com.bitgo.randombytes;
+
+import com.facebook.react.bridge.ReactMethod;
+import com.facebook.react.bridge.ReactApplicationContext;
+import com.facebook.react.bridge.Callback;
+
+import com.facebook.react.bridge.ReactContextBaseJavaModule;
+
+import java.security.SecureRandom;
+
+import android.util.Base64;
+
+class RandomBytesModule extends ReactContextBaseJavaModule {
+
+  public RandomBytesModule(ReactApplicationContext reactContext) {
+    super(reactContext);
+  }
+
+  @Override
+  public String getName() {
+    return "RNRandomBytes";
+  }
+  @ReactMethod
+  public void randomBytes(int size, Callback success) {
+    SecureRandom sr = new SecureRandom();
+    byte[] output = new byte[size];
+    sr.nextBytes(output);
+    String string = Base64.encodeToString(output, Base64.DEFAULT);
+    success.invoke(null, string);
+  }
+}

android/src/main/java/com/bitgo/randombytes/RandomBytesPackage.java

@@ -0,0 +1,34 @@
+package com.bitgo.randombytes;
+
+import com.facebook.react.ReactPackage;
+import com.facebook.react.bridge.JavaScriptModule;
+import com.facebook.react.bridge.NativeModule;
+import com.facebook.react.bridge.ReactApplicationContext;
+import com.facebook.react.uimanager.ViewManager;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+public class RandomBytesPackage implements ReactPackage {
+
+  @Override
+  public List<NativeModule> createNativeModules(
+                              ReactApplicationContext reactContext) {
+    List<NativeModule> modules = new ArrayList<>();
+
+    modules.add(new RandomBytesModule(reactContext));
+
+    return modules;
+  }
+
+  @Override
+  public List<ViewManager> createViewManagers(ReactApplicationContext reactContext) {
+    return Collections.emptyList();
+  }
+
+  @Override
+  public List<Class<? extends JavaScriptModule>> createJSModules() {
+    return Collections.emptyList();
+  }
+}