* Renamed UAlphabet unit as UInitialLetter and completely rewrote and simplified it.
* Modified units using UInitialLetter unit as necessary re changes.
* Modified TAlphaGroupItem and TAlphaGrouping to accept any upper case Unicode character instead of just "A".."Z" and "_". Uses natural sorting so, for example "Ö" sorts between "O" and "P". Now scans all snippets to build list of initial letters.