Property Implementation

`BEGIN_PROPERTY`	Begins the implementation of a property.
`END_PROPERTY`	Ends the implementation of a property.
`PLENGTH`	Returns the length of the string value the property must be set to.
`PROP`	Returns a pointer to the value the property must be set to.
`PSTRING`	Returns the address of the string value the property must be set to.
`READ_PROPERTY`	Returns if the property implementation was called for reading.
`VPROP`	Returns the value the property must be set to.