Adding a gradle build file.

Change-Id: I0c829b80f04d20d5f53d29748fa902c74586e365
diff --git a/build.gradle b/build.gradle
new file mode 100644
index 0000000..f29bf0d
--- /dev/null
+++ b/build.gradle
@@ -0,0 +1,9 @@
+apply plugin: 'java'
+
+sourceSets {
+    main {
+        java {
+            srcDirs = ['ri/src/main/java']
+        }
+    }
+}