"Sat, 14 Feb 1970 00:19:40"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700214
Only TIME
00:19:40
General datetime
1970-02-14 00:19:40Z
For Database
1970-02-14 00:19:40
For HTTP1.1
Sat, 14 Feb 1970 00:19:40 GMT