Merge pull request #635 from mwoodiupui/DS-2128

[DS-2128] Eliminate dspace.cfg:db.name

dspace-api/src/main/java/org/dspace/content/Bitstream.java

@@ -531,11 +531,7 @@ public class Bitstream extends DSpaceObject
      */
     void delete() throws SQLException
     {
-        boolean oracle = false;
-        if ("oracle".equals(ConfigurationManager.getProperty("db.name")))
-        {
-            oracle = true;
-        }
+        boolean oracle = DatabaseManager.isOracle();
 
         // changed to a check on remove
         // Check authorisation