Fix session.save() for cookie sessions, add vcsserver/rc_license stubs

- Guard all session.save() calls with hasattr checks for CookieSession
  compatibility (CookieSession auto-saves via response callbacks)
- Guard beaker-specific _set_cookie_expires and _update_cookie_out in
  login views
- Defer ldap scope_labels to property to avoid class-level AttributeError
  when python-ldap is not installed
- Add vcsserver stub package to allow imports without full vcsserver
- Add rc_license stub for CE edition (no license management)

rhodecode/authentication/plugins/services/ldap_dao.py

@@ -19,11 +19,17 @@ except ImportError:
 class LdapDao(AuthLdapBase):
     default_tls_cert_dir = "/etc/openldap/cacerts"
 
-    scope_labels = {
-        ldap.SCOPE_BASE: "SCOPE_BASE",
-        ldap.SCOPE_ONELEVEL: "SCOPE_ONELEVEL",
-        ldap.SCOPE_SUBTREE: "SCOPE_SUBTREE",
-    }
+    @staticmethod
+    def _scope_labels():
+        return {
+            ldap.SCOPE_BASE: "SCOPE_BASE",
+            ldap.SCOPE_ONELEVEL: "SCOPE_ONELEVEL",
+            ldap.SCOPE_SUBTREE: "SCOPE_SUBTREE",
+        }
+
+    @property
+    def scope_labels(self):
+        return self._scope_labels()
 
     def __init__(
         self,