When creating a snapshot, prompt the user if the snapshot's name already exists
Show what device a volume is attached to
Attempt to catch SSH requests which fail with a SocketException or SshException
Turns out a volume's snapshotId can be retrieved directly. No need for a tag
UptimeTimer is now on background thread, so won't lock the UI if it can't connect
InstanceClient deals with lost connections better than it did.

Although it's probably not rock-solid yet
README updates