NewConnectionID isn't global unique

[cnlangzi]

blobber/code/go/0chain.net/blobbercore/allocation/workers.go

Line 300 in 44b88fb

func newConnectionID() string {

connection_id is primary key in blobber's database. But NewConnectionID isn't global unique. It is a simple random number. It will make a lot of upload fail when blobber is running for long time.

func NewConnectionId() string {
nBig, err := rand.Int(rand.Reader, big.NewInt(0xffffffff))
if err != nil {
panic(err)
}
return fmt.Sprintf("%d", nBig.Int64())
}

linked to 0chain/gosdk#178

[kushthedude]

Use uuid here rather than any random number generator.