Add list_spaces
This commit and all previous that I have authored are signed off by me

Signed-off-by: Derek Chiang <derekchiang93@gmail.com>
Add list-spaces command
Add server-* commands to hyperdex.cc
Update th to 7bb34155...
Add quiet flags to stress tests.
Merge branch 'add-list-spaces' of https://github.com/derekchiang/HyperDex

* 'add-list-spaces' of https://github.com/derekchiang/HyperDex:
  Add list-spaces command
  This commit and all previous that I have authored are signed off by me
  Add list_spaces
Tidy up merge