Ticket #29 (closed task: fixed)

Description

• rename python-upnp to coherence
• move everything UPnP related into an upnp directory
• create there directories for devices and server and client services (?)
• create a backend directory
• create a plugins directory
• create a tests directory
• create a doc directory and an examples directory therein
• maybe later create a zeroconf directory similar to the upnp directory

coherence
 |
 |---- upnp
 |      |
 |      |---- devices
 |      |---- services
 |             |
 |             |---- servers(?)
 |             |---- clients(?)
 |      
 |---- backends
 |---- plugins
 |---- tests
 |---- docs
 |      |
 |      |---- examples
 |
 |-?-- zeroconf
 |      |
 |      |---- devices
 |      |---- services
 |             |
 |             |---- servers(?)
 |             |---- clients(?)