added cz/sk characters with caron

New characters with caron and ring above, which iMon VFD can't handle has been converted to particular basic characters.

But I'm thinking about making another file (i.e _a03 or something) where all characters with diacritical signs will be converted to basic ones because in come combinations this shall be awful. For example word "záložka" will be converted to "zálozka" and in this case "zalozka" is way better.