Fix allowed min datetime range on dateime fields

[sunlix]

Hi,

I have installed ProFTPd-Admin on my current MariaDB 10.4.20 (bundled with XAMPP and PHP 7.4).
But importing the table.sql as mentioned in the installation guide the database will reject the import due to wrong default dateime value.

From the MariaDB knowledge base

MariaDB stores values that use the DATETIME data type in a format that supports values between 1000-01-01 00:00:00.000000 and 9999-12-31 23:59:59.999999

The default settings are to not have NO_ZERO_DATE set.
So I think it is useful to arrange that here.

Feel free to accept the PR :)

regards
Sven

[sunlix]

That should fox #54