Bug 187201 DTE should give out 4 API for CrossTab sort and filter
DTE should give out 4 API for CrossTab sort and filter. 2 apis are used by giving out the available binding for CrossTab sort and filter. The third is api used by giving out the member value viewer is available. The fourth api is used by giving out the available value list about the memeber value.
data/org.eclipse.birt.report.data.adapter/src/org/eclipse/birt/report/data/adapter/api/DataRequestSession.java
* prepare( query, null). The default session application context is used
	 * for this query.
	 * 
	 * @param querySpec
	 *            Specifies the data access and data transforms services needed
	 *            from DtE to produce a set of query results.
	 * @return The <code>IPreparedQuery</code> object that contains a prepared
	 *         query ready for execution.
	 * @throws BirtException
	 *             if error occurs during the preparation of querySpec
	 */
	public abstract IPreparedQuery prepare( IQueryDefinition query )
			throws BirtException;
	
	/**
	 * Provides a hint to DtE that the consumer is done with the given data
	 * source, and that its resources can be safely released as appropriate.
	 * This tells DtE that there is to be no more query in this session that
	 * uses such data source.
	 * 
	 * @param dataSourceName
	 *            The name of a data source. The named data source must have
	 *            been previously defined.
	 */
	public abstract void closeDataSource( String dataSourceName )
			throws BirtException;
	
	/**
	 * Delete the cache content of the specified data set. Subsequent requests
	 * using this data set will cause its cache to be regenerated with updated