Synnefo

Automatic private networks subnet assignment in ui

Automatically choose a subnet that doesn't already exists in user's
private networks if 'Auto' subnet option is selected.

UI quota limit handling

ui inititalization process now includes a call to the introduced
`ui.views.userquota` view which returns a json representation of available user
quota limits. Quota information is used across ui to prevent user from the
effort of trying to allocate additional resources.

UI vm connection improvements

- add configurable vm hostname template
- allow override of vm connect messages
- replace ip by hostname in vm connection messages
- configurable ssh message template
- optional setting to append extra content in windows rdp files

Proper image ssh support identification

additionally check osfamily image tag. If tag set to linux enable ssh
keys support.

Fix nic add/remove handling

apply nic network state changes only after successful api calls.