Fix direct links to binaries in case of shibboleth

2017-12-07 11:21:18,978 ERROR [http-bio-0.0.0.0-8080-exec-8] [org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/nuxeo].[Nuxeo Downloader]] Servlet.service() for servlet [Nuxeo Downloader] in context with path [/nuxeo] threw exception [java.lang.IllegalStateException: No active session context] with root cause
java.lang.IllegalStateException: No active session context
	at org.jboss.seam.web.Session.instance(Session.java:111)
	at org.nuxeo.ecm.platform.shibboleth.auth.exceptionhandling.ShibbolethSecurityExceptionHandler.handleAnonymousException(ShibbolethSecurityExceptionHandler.java:60)
	at org.nuxeo.ecm.platform.web.common.exceptionhandling.NuxeoSecurityExceptionHandler.handleException(NuxeoSecurityExceptionHandler.java:69)
	at org.nuxeo.ecm.platform.web.common.exceptionhandling.NuxeoExceptionFilter.handleException(NuxeoExceptionFilter.java:69)
	at org.nuxeo.ecm.platform.web.common.exceptionhandling.NuxeoExceptionFilter.doFilter(NuxeoExceptionFilter.java:78)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at org.nuxeo.ecm.platform.web.common.encoding.NuxeoEncodingFilter.doFilter(NuxeoEncodingFilter.java:73)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:423)
	at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1079)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625)
	at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:748)