Add a configuration to hamcrest-library build.gradle

Change-Id: I12dc1bc590455ad813f16ffc831817346a4979e9
diff --git a/library/build.gradle b/library/build.gradle
index 54ab15f..3584fb1 100644
--- a/library/build.gradle
+++ b/library/build.gradle
@@ -8,6 +8,22 @@
     }
 }
 
+configurations {
+    ast
+}
+
 dependencies {
     compile project(':hamcrest')
+    ast project(':android-support-test')
+}
+
+task astJar(type: Jar) {
+    from sourceSets.main.output
+    dependsOn classes
+    baseName "hamcrest-library"
+    classifier "ast"
+}
+
+artifacts {
+    ast astJar
 }