Gns 40

Main changes:

 * Completed image lifecycle
 * new instance state to distinguish between image is running and gns3-server is running
 * stub procedure for SSH connections
 * moved gns3-ias url to settings 
 * added -gns3 suffix to image and keypair names
I think we should keep our host keys separate from the user host keys.  If we do what you currently have written, we will be adding host keys for the user without their knowledge.

After using GNS3 for long enough, the user will get host key collisions when Rackspace reuses an ip address for a new GNS3 instance. Eg:
- Rackspace creates an instance for us with ip 1.2.3.4, we auto add the host key.
<time passes>...
- Rackspace creates an instance for us with ip 1.2.3.4, the host key is now different from what we have stored.  Now we error out because of a host key mismatch.

Is there any way we can store the host key alongside the private and public keys?  It would be a great solution to this problem