Week 5: NVMe controller emulator

[Shunsuke Mie]

Hello all,

I have implemented NVM read command in this week. A NVMe controller
emulator can read backing file as below command.
$ cat /dev/nvme0ns1
However, this implementation lack functions and has come bugs.

I'll fix read command and parallel using pthread. Moreover, I try to
implement flush command until next Wednesday (~7/12).

regards,
Shunsuke Mie