This comes at the cost of that we no longer CR/LF encode literal data before encryption/signing.
That means that applications that rely on PGPainless to do the CR/LF encoding must manually
do the encoding before feeding the message to PGPainless.
The newly introduced CRLFGeneratorStream has documentation on how to do that.
Fixes#264
By default we ignore SignerUserId subpackets on signatures.
This behavior can be changed by calling Policy.setSignerUserIdValidationLevel().
Right now, STRICT and DISABLED are available as options, but it may make sense to implement
another option PARTIALLY, which will accept signatures made by key with user-id 'A <foo@bar>'
but where the sig contains a signer user id of value 'foo@bar' for example.