Adding NAT class
Includes automatic NAT feature (mn --nat) and addNAT convenience method for topologies
fixes #111
Adding NAT class
Includes automatic NAT feature (mn --nat) and addNAT convenience method for topologies
fixes #111
undoing gateway in net and removing addNAT helpers
adding internet / nat example
more NAT cleanup of net and topo
fixing --nat option in mn
small fixes for NAT
Add a timeout parameter to the pingAll command
Add ability for for OVS switch start connect to controllers using protocols other than TCP.

    net.addController( 'c0', protocol='ssl' )

This now allows OVS to connect to a controller using SSL.  The default of protocol is 'tcp'
as it currently is.
Merge pull request #305 from ggee/ovsssl

OVS switch connect to controllers using protocols other than TCP like SSL.
Merge pull request #303 from jhall11/pingall

Add a timeout parameter to the pingAll command
IVSSwitch: support batch shutdown

Not a single command like the OVS one, but it still greatly decreases the
shutdown time.

This does assume that stop() is called after batchShutdown(), which is true in
the current mininet code.
net: allow batch shutdown of multiple types of switches

Each switch class will be called to shutdown its own instances.
IVSSwitch: add an option to control the --verbose flag
adding ovs version detection to fix port numbering bug
rearranged code for elegance
removing debugging messages
conforming to mininet python style
Merge pull request #309 from rlane/ivs-batch-shutdown

support batch shutdown for IVS
Merge pull request #310 from rlane/ivs-verbose

IVSSwitch: add an option to control the --verbose flag