Handle all Oracle Timestamp types and fix milliseconds

a19b9e0 partially handles the additional types "TIMESTAMP WITH TIME ZONE" and "TIMESTAMP WITH LOCAL TIME ZONE".  The timezone data itself is still ignored, and all times are treated as UTC (incorrect, but functional).  Previously, executing `SELECT systimestamp FROM dual` caused the following error:
```
[Error: CreateColumnsFromResultSet: Unhandled oracle data type: 188]
```

47dbeed fixes setting milliseconds on the V8 date object.