C++ Binding: changes for version 1.0d

The following changes were made between versions 1.0c and 1.0d of the ZOOM C++ binding:

1. Discarded the recordSyntax prefix from recordSyntax's enumeration values.
2. Discarded the class Z3950, which was a misunderstanding all along - it existed only to carry static methods, and so was irrelevant once the namespace was introduced. Moved its methods into the top level of the ZOOM namespace.
3. Renamed connection::search()'s query argument from srch to q.
4. Renamed prefixQuery constructor's argument from search to pqn.
5. Added class CLLQuery, a subtype of query.
6. Removed the old getRecord() and getRecords() methods from the resultSet, leaving only one record-retrieval method: the API-compliant version of getRecords() first introduced in version 1.0c.
7. Renamed resultSet::getRecords()'s sz argument to size.
8. Removed the commented-out recsyn() method from the MARCRecord class.
9. Removed the extraneous int errcode parameter from the systemError interface.
10. Fixed various comments that had previous referred to the Z3950 namespace instead of ZOOM.