Negative integers are always encoded as INT8

[laufhannes]

var_dump(UBJSON::decode(UBJSON::encode(-129)));
// out: int(127)

because of

php-ubjson/UBJSON.php

Lines 166 to 181 in 137001f

	if (256 > $numeric) {
	$swap = false;
	if (0 < $numeric) {
	$result = self::UINT8;
	$pack = 'C';
	} else {
	$result = self::INT8;
	$pack = 'c';
	}
	} elseif (32768 > $numeric) {
	$result = self::INT16;
	$pack = 's';
	} elseif (2147483648 > $numeric) {
	$result = self::INT32;
	$pack = 'l';
	}