Jill: Increment Jack library version

We need to increment it every time we break the compatibility with the
Jayce format, or else Jack will print an "invalid format" error.
Jayce version has been incremented in
59c013d6d7cb2541637b341f9d01f744241a6038

Change-Id: Icd708cbe41dfcfce1df41347a9c7a564f6ed2ac9
diff --git a/jill/src/com/android/jill/frontend/java/JavaTransformer.java b/jill/src/com/android/jill/frontend/java/JavaTransformer.java
index 129922f..d7b536e 100644
--- a/jill/src/com/android/jill/frontend/java/JavaTransformer.java
+++ b/jill/src/com/android/jill/frontend/java/JavaTransformer.java
@@ -52,7 +52,7 @@
   private static final String LIB_MAJOR_VERSION = "2";
 
   @Nonnull
-  private static final String LIB_MINOR_VERSION = "2";
+  private static final String LIB_MINOR_VERSION = "3";
 
   @Nonnull
   private static final String JAYCE_MAJOR_VERSION = "3";