Add ability to set :joyent_version in knife.rb
README change
Add network API support

Joyent API version 7 allows for listing networks and for
creating zones on a particular network.
Specify modified Fog source for gembundler
Merge pull request #1 from AlainODea/network_api_support

Specify modified Fog source for gembundler
Add public/private, point Gemfile to fog/fog -- #49 Network API Support