Bug 214204 Only document content in document folder should be removed.[0601]
Description: Only document related content in document folder should be removed. Build number:2.3.0.v20080103 Steps to reproduce: 1. Deploy BIRT. 2. Edit web.xml to set BIRT_VIEWER_DOCUMENT_FOLDER to your local path and there are content inside the path. 3. Start server and click View Example to preview sample report. Expected result: Only content created by viewer should be removed in specified document folder. Actual result: All contents are deleted despite whether they are related with BIRT. Error log:n/a
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/utility/ParameterAccessor.java
* URL parameter name to indicate the resource folder of all the report
	 * resources.
	 */
	public static final String PARAM_RESOURCE_FOLDER = "__resourceFolder"; 
	/**
	 * URL parameter name to indicate the target servlet pattern.
	 */
	public static final String PARAM_SERVLET_PATTERN = "__pattern"; 
	/**
	 * URL parameter name to indicate the target window.
	 */
	public static final String PARAM_TARGET = "__target"; 
	/**
	 * URL parameter name to indicate whether cache the parameter.
	 */
	public static final String PARAM_NOCACHE_PARAMETER = "__nocache"; 
	/**
	 * URL parameter name to indicate if open document as attachment(default is
	 * inline ).
	 */
	public static final String PARAM_AS_ATTACHMENT = "__asattachment"; 
	/**
	 * URL parameter name to indicate the execution name.
	 */
	public static final String PARAM_ACTION = "__action"; 
	/**
	 * URL parameter name to indicate the client DPI setting.
	 */
	public static final String PARAM_DPI = "__dpi"; 
	/**