Add implementation for more JDBC features 

This pull request improve ola4j/Mondrian compatibility.

Mondrian use many features of the DatabaseMetaData interface.

This pull request implements missing features of the JDBC connector :

```
public ResultSet getSchemas() throws SQLException
public ResultSet getSchemas(String catalog, String schemaPattern) throws SQLException
public ResultSet getTables(String catalog, String schemaPattern, String tableNamePattern, String[] types)
```
This PR also fixes some incorrect values returned by DatabaseMetaData interface.