Speed-up of encoding (4 times faster than 2.0.1).
Added optional `mapcode_countrynames.h`, with the English short names, formal names,
and name variants of all territories.
Added optional `mapcode_countrynames_short.h` with only the short English names and
name variants.
Stricter processing of high-precision letters (now fails on illegal high-precision
letters, which includes the letter Z).
Fix to allow illegal letters "i" and "o" in Hindi, Bengali, Tibetan and Gurmukhi
(so they can later be interpreted as digits 1 and 0).
Fix for some unrecognized aliases in `convertTerritoryIsoNameToCode()`.
