(fixes #150) fixed bug that the params data type in which checkdate() function cannot understand is changed.
(fixes #150) fixed bug that the params data type in which checkdate() function cannot understand is changed.

nishizoe/OpenPNE3,upsilon/travis-test,nise-nabe/ppcon-sns,tejima/OP3PKG,upsilon/OpenPNE3,kashiwasan/symfony-advanced,tejima/testravis,nise-nabe/ppcon-sns,isaosano/OpenPNE3,tejimaya/OpenPNE3,isaosano/OpenPNE3,isaosano/OpenPNE3,nishizoe/OpenPNE3,upsilon/OpenPNE3,C-nakajima/OpenPNE3,ShinichiU/AuthFramework,tejima/testravis,balibali/KakiageSNS,openpne/OpenPNE3,kashiwasan/symfony-advanced,ShinichiU/OpenPNE3,isaosano/OpenPNE3,tejima/OP3PKG,upsilon/travis-test,C-nakajima/OpenPNE3,C-nakajima/OpenPNE3,ShinichiU/OpenPNE3,ShinichiU/OpenPNE3_with_webInstaller,openpne/OpenPNE3,balibali/KakiageSNS,tejima/testravis,openpne/OpenPNE3,tejimaya/OpenPNE3,ShinichiU/OpenPNE3,ShinichiU/OpenPNE3,C-nakajima/OpenPNE3,ShinichiU/AuthFramework,ShinichiU/AuthFramework,ShinichiU/OpenPNE3_with_webInstaller,openpne/OpenPNE3