This patch adds a new subdirectory "mh" under vmware_nsx/nsxlib/
and moves all current vmware_nsx/nsxlib/*.py to "mh". This will
make vmware_nsx/nsxlib/ consisted of only mh and v3 subdirectories.
This is part of new vmware_nsx directory structure proposed in
https://goo.gl/GdWXyH.
Change-Id: I31e4558b648c9982208739b19623002e1fa181ff