"Mon, 09 Feb 1970 00:20:18"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700209
Only TIME
00:20:18
General datetime
1970-02-09 00:20:18Z
For Database
1970-02-09 00:20:18
For HTTP1.1
Mon, 09 Feb 1970 00:20:18 GMT