Tune nfs mount options

default:
  $ dd if=/dev/zero of=/vagrant/testio bs=16k count=16k
  268435456 bytes (268 MB) copied, 16.0032 s, 16.8 MB/s

  $ dd if=/vagrant/testio of=/dev/null bs=16k count=16k
  268435456 bytes (268 MB) copied, 6.36017 s, 42.2 MB/s

noatime,rsize=16384,wsize=16384:
  $ dd if=/dev/zero of=/vagrant/testio bs=16k count=16k
  268435456 bytes (268 MB) copied, 10.5531 s, 25.4 MB/s

  $ dd if=/vagrant/testio of=/dev/null bs=16k count=16k
  268435456 bytes (268 MB) copied, 6.30286 s, 42.6 MB/s

noatime,rsize=32767,wsize=32767:
  $ dd if=/dev/zero of=/vagrant/testio bs=32k count=8k
  268435456 bytes (268 MB) copied, 8.80528 s, 30.5 MB/s

  $ dd if=/vagrant/testio of=/dev/null bs=32k count=8k
  268435456 bytes (268 MB) copied, 6.2102 s, 43.2 MB/s

Change-Id: I0581463dc219c2dd454fd436c7abe40be68cc6e3