PropertyHandle :: CanAccess - Is property handle accessible

The function checks whether the property handle is accessible or not. The function returns NO, when property handle is not accessible. There are several reasons for denying access:

1. The current application does not have rights for accessing the property (disabled by context)
2. The property handle is not selected (for subordinated property handles, only)
3. The property handle is invalid.
4. No instance selected (when sel_opt is true)