Added journal=true back into MongoDB connection string. For now, the...

Added journal=true back into MongoDB connection string.  For now, the connection string will contain both "j" and "journal", until such time as the MongoDB Java driver supports "journal".

mongodb/src/main/java/com/yahoo/ycsb/db/OptionsSupport.java

@@ -76,7 +76,8 @@ public final class OptionsSupport {
                 result = addUrlOption(result, "w", "1");
             }
             else if ("journaled".equals(writeConcernType)) {
-                result = addUrlOption(result, "j", "true");
+                result = addUrlOption(result, "journal", "true"); // this is the documented option name
+                result = addUrlOption(result, "j", "true");       // but keep this until MongoDB Java driver supports "journal" option
             }
             else if ("replica_acknowledged".equals(writeConcernType)) {
                 result = addUrlOption(result, "w", "2");

mongodb/src/test/java/com/yahoo/ycsb/db/OptionsSupportTest.java

@@ -110,7 +110,7 @@ public class OptionsSupportTest {
         assertThat(
                 updateUrl("mongodb://locahost:27017/?foo=bar",
                         props("mongodb.writeConcern", "journaled")),
-                is("mongodb://locahost:27017/?foo=bar&j=true"));
+                is("mongodb://locahost:27017/?foo=bar&journal=true&j=true"));
         assertThat(
                 updateUrl("mongodb://locahost:27017/?foo=bar",
                         props("mongodb.writeConcern", "replica_acknowledged")),