Defines page-wide attributes.
<%@ page attribute="value" ... %>
attributes, with default values, are:
attribute = language="java" | session="true"
| contentType=text/html;charset="ISO-8859-1"
| import="package(s)" | buffer="8kb"
| autoflush="true" | isThreadSafe="true"
| info="text_string" | errorPage="relativeURL" | isErrorpage="true" | extends="class_name"
value = a string literal in single or double quotes.