Missing accents for vowels

[ghost]

It would be very helpful to have more accents available (especially à, è, ë, û, ô).

[RigacciOrg]

Requested accented vowels for Italian (minimum): àèéìòù. Beside the minimum, both grave and acute versions are desiderable.

[DenSA-Inc]

I'm adding "ß" to the list, a variant of "s" in the german language

[VladThodo]

Thanks for your suggestions. I'm working on implementing this accents as well as the accents mentioned in #24.