If a translation file contains two copies of the same English string,
with the same translation, then we don't care at all; just throw out
the second copy.
If a translation file contains two copies of the same English string,
with DIFFERENT translations, then (according to how the game does
translation) one of those translations must be inappropriate. Give
a warning in that case; and again, throw out the second copy because
we are forced to pick ONE translation for use within the game.
Also fix some minor typos I noticed in the strings.
All these messages now consistently use the phrase "go back".
Before:
int transcompleteness[NUMLAN] = {2057, 2057, 1229, 2053, 2053, 1555, 384, };
After:
int transcompleteness[NUMLAN] = {2051, 2051, 1227, 2047, 2047, 1551, 383, };
