Clean up multidex gradle build, bump version to 1.0.2 for release

Bug: 36122649
Test: ./gradlew dist test connectedAndroidTest
Change-Id: I79578f683146a3ea16521cd090d113698a14c5f5
diff --git a/PREUPLOAD.cfg b/PREUPLOAD.cfg
new file mode 100644
index 0000000..2811ea9
--- /dev/null
+++ b/PREUPLOAD.cfg
@@ -0,0 +1,6 @@
+[Hook Scripts]
+checkstyle_hook = ${REPO_ROOT}/prebuilts/checkstyle/checkstyle.py --sha ${PREUPLOAD_COMMIT}
+
+[Builtin Hooks]
+commit_msg_changeid_field = true
+commit_msg_test_field = true