PoE switched from FNV to murmur hash

[beevik]

In league 3.21, PoE appears to have changed their name hashing algorithm from FNV to MurmurHash. I added this function to index.go and started calling it instead of FNV. This seemts to have fixed the incompatibility.

func murmurHash(path string) uint64 {
	const (
		seed    = 0x1337b33f
		initial = 0xc6a4a7935bd1e995
		r       = 47
	)

	path = strings.ToLower(path)
	path = strings.TrimRight(path, "/\\")
	b := []byte(path)
	m := uint64(initial)
	h := seed ^ (uint64(len(b)) * m)
	for len(b) >= 8 {
		k := binary.LittleEndian.Uint64(b[:8])
		b = b[8:]
		k *= m
		k = (k ^ (k >> r)) * m
		h = (h ^ k) * m
	}

	if len(b) > 0 {
		k := uint64(0)
		for i := len(b) - 1; i >= 0; i-- {
			k = (k << 8) | uint64(b[i])
		}
		h = (h ^ k) * m
	}

	h = (h ^ (h >> r)) * m
	h = h ^ (h >> r)
	return h
}