Add android.jar to root project and use during jme-android project build.

Current version is rev19, KitKat.

jme3-android/build.gradle

@@ -5,5 +5,5 @@ if (!hasProperty('mainClass')) {
 dependencies {
     compile project(':jme3-core')
     compile project(':jme3-plugins')
-    compile 'com.google.android:android:4.1.1.4'
+    compile files('../lib/android.jar')
 }