"Wed, 18 Feb 1970 21:42:03"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700218
Only TIME
21:42:03
General datetime
1970-02-18 21:42:03Z
For Database
1970-02-18 21:42:03
For HTTP1.1
Wed, 18 Feb 1970 21:42:03 GMT