DATACOUCH-328 - Fix document expiry when using expressions

When using an expiry expression with TimeUnit.DAYS larger than 30 days
the document expiry is not correctly set.

Original pull request: #150.

src/main/java/org/springframework/data/couchbase/core/mapping/BasicCouchbasePersistentEntity.java

@@ -109,7 +109,7 @@ public class BasicCouchbasePersistentEntity<T> extends BasicPersistentEntity<T,
       Calendar cal = Calendar.getInstance(TimeZone.getTimeZone("UTC"));
       if (annotation.expiryUnit() == TimeUnit.DAYS) {
         //makes sure we won't lose resolution
-        cal.add(Calendar.DAY_OF_MONTH, annotation.expiry());
+        cal.add(Calendar.DAY_OF_MONTH, expiryValue);
       } else {
         //use the shift in seconds since resolution should be smaller
         cal.add(Calendar.SECOND, (int) secondsShift);