adding linuxrouter.py
adding vlanhost.py
adding documentation and test for linuxrouter.py
linuxrouter.py: changing name, printing routing table, and some more documentation
chmod +x vlanhost.py
adding test for vlanhost.py and adding vlantopo example
Merge pull request #361 from mininet/devel/linuxrouter

Adding LinuxRouter to Examples
Merge pull request #362 from mininet/devel/vlanhost

Adding VLANHost to Examples
adding comment to VLANStarTopo in vlanhost.py
Merge branch 'master' of https://github.com/mininet/mininet into feature/modularize-backend