add views, templates and static files.
Merge pull request #2 from yuta-hamada/ryu-gui

add views, templates and static files.
update client modlues. 2013-3-26
Merge pull request #3 from yuta-hamada/ryu-gui

update client modlues. 2013-3-26
lib/port_no: handling port_no as string
topology: exported function returns Switch/Link list instead of event
topology: Add REST API