[build] Added gradle build script

.gitignore

@@ -1,7 +1,9 @@
 bin/
 gen/
+build/
 .settings/
 
+.DS_Store
 .classpath
 .cproject
 .project

lib/build.gradle

@@ -0,0 +1,27 @@
+apply plugin: 'android-library'
+
+dependencies {
+    compile fileTree(dir: 'libs', include: '*.jar')
+}
+
+android {
+    compileSdkVersion 18
+    buildToolsVersion "18.0.1"
+
+    sourceSets {
+        main {
+            manifest.srcFile 'AndroidManifest.xml'
+            java.srcDirs = ['src']
+            resources.srcDirs = ['src']
+            aidl.srcDirs = ['src']
+            renderscript.srcDirs = ['src']
+            res.srcDirs = ['res']
+            assets.srcDirs = ['assets']
+        }
+
+        instrumentTest.setRoot('tests')
+
+        debug.setRoot('build-types/debug')
+        release.setRoot('build-types/release')
+    }
+}