Regenerate gemspec for version 2.3.4
Regenerate gemspec for version 2.3.4

Windermere/rubycas-client,rubycas/rubycas-client,identification-io/rubycas-client,angjunwen/rubycas-client,angjunwen/rubycas-client,lsylvester/rubycas-client,geo767/rubycas-client