adjust ddl statements for oracle

since two long columns are not permitted in one table by oracle and the
datatype long is deprecated, the respective columns are changed to clob

src/plugins/monitoring/src/database/monitoring_oracle.sql

@@ -35,8 +35,8 @@ CREATE TABLE ofMessageArchive (
    toJID             VARCHAR2(1024)   NOT NULL,
    toJIDResource   VARCHAR2(255)      NULL,
    sentDate          INTEGER          NOT NULL,
-   stanza			 LONG			  NULL,
-   body              LONG
+   stanza			 CLOB			  NULL,
+   body              CLOB
 );
 CREATE INDEX ofMessageArchive_con_idx ON ofMessageArchive (conversationID);