directory structure change to work with glide

glide has its own requirements. My previous workaround caused me some
code checkin errors. Need to fix this.

weed/util/bytes.go

@@ -0,0 +1,45 @@
+package util
+
+// big endian
+
+func BytesToUint64(b []byte) (v uint64) {
+	length := uint(len(b))
+	for i := uint(0); i < length-1; i++ {
+		v += uint64(b[i])
+		v <<= 8
+	}
+	v += uint64(b[length-1])
+	return
+}
+func BytesToUint32(b []byte) (v uint32) {
+	length := uint(len(b))
+	for i := uint(0); i < length-1; i++ {
+		v += uint32(b[i])
+		v <<= 8
+	}
+	v += uint32(b[length-1])
+	return
+}
+func BytesToUint16(b []byte) (v uint16) {
+	v += uint16(b[0])
+	v <<= 8
+	v += uint16(b[1])
+	return
+}
+func Uint64toBytes(b []byte, v uint64) {
+	for i := uint(0); i < 8; i++ {
+		b[7-i] = byte(v >> (i * 8))
+	}
+}
+func Uint32toBytes(b []byte, v uint32) {
+	for i := uint(0); i < 4; i++ {
+		b[3-i] = byte(v >> (i * 8))
+	}
+}
+func Uint16toBytes(b []byte, v uint16) {
+	b[0] = byte(v >> 8)
+	b[1] = byte(v)
+}
+func Uint8toBytes(b []byte, v uint8) {
+	b[0] = byte(v)
+}