Bug 149617 Support Content-type-based editor lookup
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/ReportPlugin.java
* @return the cheat sheet property preference, stored in the workbench root
	 */
	public static boolean readCheatSheetPreference( )
	{
		IWorkspace workspace = ResourcesPlugin.getWorkspace( );
		try
		{
			String property = workspace.getRoot( )
					.getPersistentProperty( new QualifiedName( "org.eclipse.birt.property", 
							"showCheatSheet" ) ); 
			if ( property != null )
				return Boolean.valueOf( property ).booleanValue( );
		}
		catch ( CoreException e )
		{
			e.printStackTrace( );
		}
		return true;
	}
	/**
	 * Set the show cheatsheet preference in workspace root. Used by wizards
	 */
	public static void writeCheatSheetPreference( boolean value )
	{
		IWorkspace workspace = ResourcesPlugin.getWorkspace( );
		try
		{
			workspace.getRoot( )
					.setPersistentProperty( new QualifiedName( "org.eclipse.birt.property", 
							"showCheatSheet" ),