Update to the latest Gradle 5.6.3 and Gradle Android plugin 3.5.1

Fix issue with ANDROID_GRADLE_TASK. Set apk file  in separate folder ( from
gradle  4.x)

dependencies/extension-api/build.gradle

@@ -3,6 +3,9 @@ buildscript {
 		jcenter {
 			url "http://jcenter.bintray.com/"
 		}
+		maven {
+			url 'https://maven.google.com/'
+		}
 	}
 	
 	dependencies {
@@ -15,4 +18,4 @@ apply plugin: 'com.android.library'
 android {
 	compileSdkVersion Integer.parseInt(project.ANDROID_BUILD_SDK_VERSION)
 	buildToolsVersion project.ANDROID_BUILD_TOOLS_VERSION
-}
+}