Property with invalid number of GET and/or SET blocks

Properties must be non empty and at most contain one block of type GET or SET.

Errouneus code example:

FUNCTION foo
    PROPERTY bar : DINT 
        // Invalid, empty (no GET or SET block)
    END_PROPERTY

    PROPERTY baz : DINT 
        // Invalid, two GET blocks
        GET END_GET
        GET END_GET
    END_PROPERTY

    PROPERTY qux : DINT 
        // Invalid, two SET blocks
        SET END_SET
        SET END_SET
    END_PROPERTY
END_FUNCTION