Special character treatment

Once a braille table has been exhausted, current processing falls over. This is not acceptable. An approach to extensions is outlined below.

If the first character of a piece of the input text is not present in the table, then the braille tables are of no use. A second step would be to use a lookup in a HashMap, mapping unicode codepoints to output strings, with a default input step distance of a single character, i.e. step over the non-matched character having processed it. The final phase (basically error handling) is to step over that character and report the error as best as possible.

I know this will not work for all character sequences, for example, processing părtīng, which contracts to p_(ar)t^(ing) where the content in braces is a contraction. These will need to be added to the main table since the match must be against the special character and a small suffix, ărt or īng in this case.