[BUG] Leap year has strange behavior

[Brano5]

When I try to set a date that is 29.2 or later in a leap year. In PLC it is set correctly, but in Onliner it has different values. As shown in image:

[Specter-13]

/cib

[IX-BOT]

Branch 203-_BUG_Leap_year_has_strange_behavior created!

[Specter-13]

Culprit

This bug occurs, when date value (DATE, LDATE, DATETIME, LDATETIME) from PLC is read over WebApi.
It happens:

1. when is a leap year and date is after 29th february
   e.g. : 05.20.2000 ( WebApi will return 05.21.2000 )

2. when is a next year after leap year before 28th february
   e.g.: 02.13.2001 (WebApi will return 02.14.2001)

3. 27th february and 28th february a year after leap year read over webapi return same value

The culprit is GetFromBinary(long value) method in corresponding WebApi primitive files (WebApiDate.cs, WebApiLDate.cs, WebApiDatetime.cs, WebapiILDatetime.cs). The returned binary value from WebApi is not correct and these inconsistencies happen.

Reproduced in this branch 203-_BUG_Leap_year_has_strange_behavior in AX_Sharp.cs test file.

Plc values are defined in ax-test-project in program.st file:

Temporary fix

Temporary not-fully fix was introduced, where date is checked for a leap year a corresponding corrections are done:
This fix is not working for dates 27th february and 28th february (a year after leap year, eg 2001), as they return same value.

@PTKu