Fixes #372

Since chroot() doesn't chdir() by default, we are left in
an unreachable directory in node.pexec() (and in xterms.)

fixes #370

Fix output of backgrounded processes

print useful output for tests upon failure

Adding VLANHost to Examples

Adding LinuxRouter to Examples

Fix UserSwitch.connected() as well as testLinkDelay() in test_hifi
We need more than one iteration since the first iteration may show reactive forwarding and ARP delay; currently we have three for good measure, although two is probably enough.

improve startup performance, largely by removing unnecessary ifconfigs

fixes #347

Adding NAT class to NodeLib

Raise exception when link incorrectly formatted

fix for controller shutdown - send SIGHUP rather than SIGKILL

Update to MiniEdit 2.2.0.1

- Replace custom code to set OF protocols with new Mininet available API to set.

Add parameter to set protocol list in OVSSwitch.

- Updated for new Mininet 2.2.0
- Support TCP or SSL for remote controller
- Support HostWithPrivateDirs Hosts

Applying @cdburkard fix to #322

fix Singleton.__call__ error