mvp: Introducing Model View Presenter pattern

libringclient is a new module where we will put avery non Android code.
MVP must not depend on Android.

app now depends on that module. It should improve reusability.

Change-Id: I20c7d7adeed43212a21e5e617e6d2b6054db8a40
Tuleap: #1217
diff --git a/ring-android/libringclient/build.gradle b/ring-android/libringclient/build.gradle
new file mode 100644
index 0000000..49df001
--- /dev/null
+++ b/ring-android/libringclient/build.gradle
@@ -0,0 +1,8 @@
+apply plugin: 'java'
+
+dependencies {
+    compile fileTree(dir: 'libs', include: ['*.jar'])
+}
+
+sourceCompatibility = "1.7"
+targetCompatibility = "1.7"