add ssl_base_url for `api' application in OpenPNE.yml.sample (fixes #3168)
add ssl_base_url for `api' application in OpenPNE.yml.sample (fixes #3168)

kashiwasan/symfony-advanced,isaosano/OpenPNE3,nishizoe/OpenPNE3,isaosano/OpenPNE3,ShinichiU/OpenPNE3,C-nakajima/OpenPNE3,nishizoe/OpenPNE3,ShinichiU/OpenPNE3,C-nakajima/OpenPNE3,ShinichiU/OpenPNE3,ShinichiU/OpenPNE3,kashiwasan/symfony-advanced,upsilon/travis-test,isaosano/OpenPNE3,isaosano/OpenPNE3,C-nakajima/OpenPNE3,C-nakajima/OpenPNE3,upsilon/travis-test