Make UUID from current time base.

Make UUID using uuid_t.

let uuid_t_size = MemoryLayout.size(ofValue: uuid_t.self)
let uuid_t_pointer = UnsafeMutablePointer<UInt8>.allocate(capacity: uuid_t_size)
uuid_generate_time(uuid_t_pointer)
let uuid_t_value = uuid_t_pointer.withMemoryRebound(to: uuid_t.self, capacity: uuid_t_size) {$0.pointee}
uuid_t_pointer.deallocate()
let uuid = UUID(uuid: uuid_t_value)