SimpleJdbcCall: Function return type (REF CURSOR) should be resolved properly.

If you need to call Oracle function like this:
```function get_foo() return ref cursor;```
you will get java.sql.SQLException: Invalid column type: 1111

For regular parameters (not for return type) there is a workaround for ref cursor (see CallMetaDataContext.java:394)

I have done this also for return type.