Switch platform to 8, to allow unbundling/backporting of GoogleAuthenticator

Change-Id: Ic7d89d382cee09c4cf07bf630ff8073a7987b65a
diff --git a/core/src/main/java/Android.mk b/core/src/main/java/Android.mk
index 7a48084..109698f 100644
--- a/core/src/main/java/Android.mk
+++ b/core/src/main/java/Android.mk
@@ -8,7 +8,7 @@
 LOCAL_SRC_FILES := \
    $(call all-java-files-under, net)
 
-LOCAL_SDK_VERSION := current
+LOCAL_SDK_VERSION := 8
 
 # Build the actual static library
 include $(BUILD_STATIC_JAVA_LIBRARY)