SIS location service is configured incorrectly

The LocationServlet.java file reads depth and capacity as properties from the web.xml file, as well as from its sis-location-config.xml file, which also redefines those properties. In addition, code in the LocationServlet.java reads the properties using ServletConfig.getInitParameter, when a better (more override-friendly method) method is to use ServletConfig.getServletContext().getInitParameter. I'll fix that.