Bug 169675 rptdocument folder should be configurable independent of the rptdesign folder
The folder in which rptdesign Report Design files are stored can be configured using the context parameters BIRT_VIEWER_WORKING_FOLDER or BIRT_VIEWER_DOCUMENT_FOLDER. But: The rptdocument files (generated temporarily during runtime) are always stored in a subfolder of the rptdesign folder called "documents". This behaviour is hard-coded. It should be configurable instead: We should have the possibility to place the rptdesign files in one folder, and the rptdocuments in a completely different folder, not necessarily a subdir of the rptdesign folder. This especially because the rptdocument files are created during run-time. In some production environments no write access is granted to the deployment dirs. In that case it would be necessary to point the rptdocument folder to some temp dir. Ideally, the environment variable "java.io.tmpdir" would be supported for this purpose as well.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/utility/ParameterAccessor.java
* Context parameter name that gives the repository location of the script
	 * files to run reports.
	 */
	public static final String INIT_PARAM_SCRIPTLIB_DIR = "BIRT_VIEWER_SCRIPTLIB_DIR"; 
	/**
	 * Context parameter name that determines the search strategy of searching
	 * report resources. True if only search the working folder, otherwise
	 * false.
	 */
	public static final String INIT_PARAM_WORKING_FOLDER_ACCESS_ONLY = "WORKING_FOLDER_ACCESS_ONLY"; 
	/**
	 * The parameter name that gives the repository lication to put the created
	 * documents and report design files.
	 */
	public static final String INIT_PARAM_DOCUMENT_FOLDER = "BIRT_VIEWER_DOCUMENT_FOLDER"; 
	/**
	 * Context parameter name that gives the absolute resource location
	 * directory.
	 */
	public static final String INIT_PARAM_BIRT_RESOURCE_PATH = "BIRT_RESOURCE_PATH"; 
	/**
	 * Context parameter name that gives preview report max rows limited.
	 */
	public static final String INIT_PARAM_VIEWER_MAXROWS = "BIRT_VIEWER_MAX_ROWS"; 
	/**
	 * Context parameter name that if always overwrite generated document file.
	 */
	public static final String INIT_PARAM_OVERWRITE_DOCUMENT = "BIRT_OVERWRITE_DOCUMENT"; 
	/**
	 * Context parameter name that defines BIRT viewer configuration file.