removed message about functions not working with dates with 0 month/d…

…ay as those dates don't exist

Signed-off-by: Matthew Wells <[email protected]>

docs/user/ppl/functions/datetime.rst

@@ -621,7 +621,7 @@ DAY
 Description
 >>>>>>>>>>>
 
-Usage: day(date) extracts the day of the month for date, in the range 1 to 31. The dates with value 0 such as '0000-00-00' or '2008-00-00' are invalid.
+Usage: day(date) extracts the day of the month for date, in the range 1 to 31.
 
 Argument type: STRING/DATE/DATETIME/TIMESTAMP
 
@@ -669,7 +669,7 @@ DAYOFMONTH
 Description
 >>>>>>>>>>>
 
-Usage: dayofmonth(date) extracts the day of the month for date, in the range 1 to 31. The dates with value 0 such as '0000-00-00' or '2008-00-00' are invalid.
+Usage: dayofmonth(date) extracts the day of the month for date, in the range 1 to 31.
 
 Argument type: STRING/DATE/DATETIME/TIMESTAMP
 
@@ -694,7 +694,7 @@ DAY_OF_MONTH
 Description
 >>>>>>>>>>>
 
-Usage: day_of_month(date) extracts the day of the month for date, in the range 1 to 31. The dates with value 0 such as '0000-00-00' or '2008-00-00' are invalid.
+Usage: day_of_month(date) extracts the day of the month for date, in the range 1 to 31.
 
 Argument type: STRING/DATE/DATETIME/TIMESTAMP
 
@@ -1128,7 +1128,7 @@ MONTH
 Description
 >>>>>>>>>>>
 
-Usage: month(date) returns the month for date, in the range 1 to 12 for January to December. The dates with value 0 such as '0000-00-00' or '2008-00-00' are invalid.
+Usage: month(date) returns the month for date, in the range 1 to 12 for January to December.
 
 Argument type: STRING/DATE/DATETIME/TIMESTAMP
 
@@ -1154,7 +1154,7 @@ MONTH_OF_YEAR
 Description
 >>>>>>>>>>>
 
-Usage: month_of_year(date) returns the month for date, in the range 1 to 12 for January to December. The dates with value 0 such as '0000-00-00' or '2008-00-00' are invalid.
+Usage: month_of_year(date) returns the month for date, in the range 1 to 12 for January to December.
 
 Argument type: STRING/DATE/DATETIME/TIMESTAMP