Method that eliminates the letters with tilde, dieresis, etc.
distance(String s1, String s2)
Implementation of Damerau-Levenshtein distance with transposition (also
sometimes calls unrestricted Damerau-Levenshtein distance).
It is the minimum number of operations needed to transform one string into
the other, where an operation is defined as an insertion, deletion, or
substitution of a single character, or a transposition of two adjacent