Added SAML2 support (#185)

* ~ in gitignore

* add config options for SAML authentication

* add information about SP metadata

* add gem for omniauth-saml

* Add the SAML strategy as a middleware

* add gem for omniauth-saml

* Send SAML request to saml module

* Pass env parameters to saml provider

* Add options for specifying saml signing certificate

* Almost there

* Re-enable SAML redirection

* Correctly map saml attributes

* change full certificate to only the fingerprint

* change full certificate to only the fingerprint

* revert changes to gitgnore

* cleanup

app/models/user.rb

@@ -55,6 +55,14 @@ class User < ApplicationRecord
     auth_hash['info']['email']
   end
 
+  def self.saml_username(auth_hash)
+    auth_hash['info']['nickname']
+  end
+  
+  def self.saml_email(auth_hash)
+    auth_hash['info']['email']
+  end
+
   def set_encrypted_id
     self.encrypted_id = "#{username[0..1]}-#{Digest::SHA1.hexdigest(uid+provider)[0..7]}"
   end