bugfix: Critical configuration errors should not enforce a baseurlpath.

The code was enforcing this option even if a configuration was passed as a parameter to the constructor. If there is something wrong with a configuration and we are passing it to the constructor, we should know if at least the 'baseurlpath' is correct, and if not, fix it somehow.

This bug was producing a default configuration without 'baseurlpath', when no configuration was passed. In that situation, only the default path (/simplesaml) was working correctly.