Bug 176681 Issue about creating context-parameter path in read-only path[0601]
Description: Issue about creating context-parameter path in read-only path Build number:2.2.0.v20070308 Steps to reproduce: 1. Deploy birt. 2. Set BIRT_VIEWER_DOCUMENT_FOLDER/BIRT_VIEWER_IMAGE_DIR/.. to a read-only path. 3. Preview report. Expected result: Because the path is read-only, folders should be created in ${java.io.tmpdir} Actual result: No folders are created in ${java.io.tmpdir} and reports cannot be previewed in frameset mode.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/utility/ParameterAccessor.java
public static final String EQUALS_OPERATOR = "="; 
	/**
	 * Suffix of report document.
	 */
	public static final String SUFFIX_REPORT_DOCUMENT = ".rptdocument"; 
	/**
	 * Report working folder.
	 */
	public static String workingFolder = null;
	/**
	 * Document folder to put the report files and created documents.
	 */
	public static String documentFolder = null;
	/**
	 * Image folder to put the image files
	 */
	public static String imageFolder = null;
	/**
	 * Log folder to put the generated log files
	 */
	public static String logFolder = null;
	/**
	 * Log level
	 */
	public static String logLevel = null;
	/**
	 * Script lib folder
	 */
	public static String scriptLibDir = null;
	/**