"Sat, 21 Feb 1970 00:19:45"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700221
Only TIME
00:19:45
General datetime
1970-02-21 00:19:45Z
For Database
1970-02-21 00:19:45
For HTTP1.1
Sat, 21 Feb 1970 00:19:45 GMT