date handling: handle "AM"/"PM" on time

And be a bitmore careful about matching: if we don't recognize a word
or a number, we skip the whole thing, rather than trying the next character
in that word/number.

Finally: since ctime() adds the final '\n', don't add another one in test-date.

test-date.c

@@ -14,7 +14,7 @@ int main(int argc, char **argv)
 		memcpy(result, "bad", 4);
 		parse_date(argv[i], result, sizeof(result));
 		t = strtoul(result, NULL, 0);
-		printf("%s -> %s -> %s\n", argv[i], result, ctime(&t));
+		printf("%s -> %s -> %s", argv[i], result, ctime(&t));
 	}
 	return 0;
 }