Fix https://issues.apache.org/bugzilla/show_bug.cgi?id=56265
Do not escape values of dynamic tag attributes containing EL expressions
Patch by kkolinko

git-svn-id: https://svn.apache.org/repos/asf/tomcat/tc7.0.x/trunk@1579218 13f79535-47bb-0310-9956-ffa450edef68