[tokenization] Adding an acronym token type for things like U.N. so we can delete internal periods on those tokens

src/scanner.c

@@ -46105,7 +46105,7 @@ yy3315:
 	}
 yy3316:
 #line 166 "scanner.re"
-	{ return ABBREVIATION; }
+	{ return ACRONYM; }
 #line 46110 "scanner.c"
 yy3317:
 	yyaccept = 6;