interface_casting.dpr makes incorrect statements about successful compilation

[phormio]

With reference to interfaces_casting.dpr:

1. If I uncomment line 83, the program doesn't compile.
2. If I uncomment line 88, the program doesn't compile.
3. The problem in both cases is the reference to the unknown identifier My. This identifier is also used on lines 68-69.

[michaliskambi]

Thank you very much for the report, fixed!

( It was supposed to be MyInterface, not just My, we did renames in 08621a1 ).