Merge pull request #3 from k1LoW/2.0

2.0
fix E_STRICT Error
Merge pull request #4 from kaz29/2.0

fix E_STRICT Error
fixed PHP5.4 E_STRICT error
Merge pull request #5 from oppara/php54

fixed PHP5.4 E_STRICT error
add datetime validation rule regex date time sec for date time fields.
Merge pull request #6 from ootatter/datetime_sec

add datetime validation rule regex date time sec for date time fields.