Merge branch 'feature/ISTWCMS-4851-tstruyk-saml-map-attributes' into '1.0.x'

ISTWCMS-4851: Add SAML Attribute mapping configuration

See merge request !37

config/install/simplesamlphp_custom_attributes.mappings.yml

-mappings: {  }
+mappings:
+  -
+    attribute_name: 'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/givenname'
+    field_name: field_uw_first_name
+  -
+    attribute_name: 'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/surname'
+    field_name: field_uw_last_name