"Fri, 20 Feb 1970 12:02:56"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700220
Only TIME
12:02:56
General datetime
1970-02-20 12:02:56Z
For Database
1970-02-20 12:02:56
For HTTP1.1
Fri, 20 Feb 1970 12:02:56 GMT