Remove papers from parsifal repo.

Parsifal papers should be in a separate repository.
Move parse_string_until from http to core/basePTypes.
Move openpgp tool into Parsifal.
Cleanup in Pkcs1 module.
Bugfix in Pkcs1.decrypt arguments.

Because X ^ d [n] is not the same as d ^ X [n]...
New option in parsifal tool: no-alias.

This allows for squashing the string produced.
New version of value_of_der_object.
Minor cleanup in kerby.

Remove useless lines.
Add libkrb5 stubs to handle kerberos decryption.
Add support for Keberos encrypted containers using libkrb5.
New container: encrypted_data_container.

The idea is to replace encrypted_data (which only handled a raw binstring).
First support for PK_INIT RSA decryption in Kerberos messages.
Add support for ticket decryption in AP_REQ messages.
Add support for some of Kerberos authorization data (PAC in particular).
Misc Kerby enum update.