Restrict sdk version to 4.20.x to fix #56 (#57)

ElvisChiang · satya164 · commit adba285a002e · 2017-04-19T12:11:32.000+05:30
diff --git a/src/android/build.gradle b/src/android/build.gradle
@@ -36,5 +36,5 @@ repositories {
 dependencies {
     compile 'com.facebook.react:react-native:+'
     compile 'com.android.support:appcompat-v7:23.1.0'
-    compile 'com.facebook.android:audience-network-sdk:4.+'
+    compile 'com.facebook.android:audience-network-sdk:4.20.+'
 }

Original file line number	Diff line number	Diff line change
`@@ -36,5 +36,5 @@ repositories {`
`36`	`36`	`dependencies {`
`37`	`37`	`compile 'com.facebook.react:react-native:+'`
`38`	`38`	`compile 'com.android.support:appcompat-v7:23.1.0'`
`39`		`- compile 'com.facebook.android:audience-network-sdk:4.+'`
	`39`	`+ compile 'com.facebook.android:audience-network-sdk:4.20.+'`
`40`	`40`	`}`