The default configuration uses a directory in /tmp, which may allow
an user to create this directory before simpleSAMLphp attempts to
create it. This can allow the user to overwrite files the webserver has
access to.

This patch changes the default directory.

git-svn-id: https://simplesamlphp.googlecode.com/svn/trunk@2084 44740490-163a-0410-bde0-09ae8108e29a