Always opt to merge dictionaries when creating a SAMFileHeaderMerger.

git-svn-id: file:///humgen/gsa-scr1/gsa-engineering/svn_contents/trunk@852 348d0f76-0448-11de-a6fe-93d51630548a

java/src/org/broadinstitute/sting/gatk/dataSources/simpleDataSources/SAMDataSource.java

@@ -181,7 +181,7 @@ public class SAMDataSource implements SimpleDataSource {
      */
     private SamFileHeaderMerger createHeaderMerger() {
         List<SAMFileReader> lst = GetReaderList();
-        return new SamFileHeaderMerger(lst, SORT_ORDER);
+        return new SamFileHeaderMerger(lst, SORT_ORDER, true);
     }