Remove the id_attr_name configuration option

The name of the id-attribute for signing, encrypting and decrypting an XML document is
well know for each of those operations. There is no need to define another.

Signed-off-by: Ivan Kanakarakis <ivan.kanak@gmail.com>

Author: c00kiemon5ter

src/saml2/config.py

@@ -69,7 +69,6 @@
     "extensions",
     "allow_unknown_attributes",
     "crypto_backend",
-    "id_attr_name",
     "delete_tmpfiles",
 ]
 
@@ -228,7 +227,6 @@ def __init__(self, homedir="."):
         self.entity_category = []
         self.entity_category_support = []
         self.crypto_backend = 'xmlsec1'
-        self.id_attr_name = None
         self.scope = ""
         self.allow_unknown_attributes = False
         self.extension_schema = {}