Make sure the `saml:IDPList` and `IDPList` parameters are not overloaded. From now on, saml:IDPList is being used when SSP is used as a proxy while the IDPList parameter is used when SSP is used as in SP-mode and you want to apply scoping to your AuthnRequest.

See https://github.com/simplesamlphp/simplesamlphp/pull/1563 for the full explanation of the changes.

Add ability to retrieve certificates or private keys from database

Use the HTML 'dir' attribute to properly indicate text direction of this
language. Browser takes care of most issues already. Use value of dir
property in css to position things in the main layout that are explicitly
right or left aligned.

Fix error messages