====== NotEmptyDateTime ======

The function NotEmptyDateTime() checks whether a date variable contains an empty value or an invalid value.
To do this, only one date variable must be specified as an argument. If their value is invalid, an empty string is returned as a result. This prevents further processing within a mapping rule set. The RuleSet is then simply skipped without an error being triggered.
It is also possible to specify a minimum date value within the function by specifying a second argument, with which the date in the first argument is to be compared. If both values are identical, the function also returns an empty string. The individual arguments should be separated by a comma.
==== Syntax: ====

<code>NotEmptyDateTime('Date')</code>
<code>NotEmptyDateTime('Date', 'min Date')</code>

==== Samples: ====

<code>NotEmptyDateTime('2014-12-15 01:00:00')</code>
provides 2014-12-15 01:00:00
<code>NotEmptyDateTime('0001-01-01 00:00:00')</code>
provides <null>
<code>NotEmptyDateTime('1975-01-01 00:00:00')</code>
provides 1975-01-01 00:00:00
<code>NotEmptyDateTime('1975-01-01 00:00:00', '1975-01-01')</code>
provides <null>