Don't offer flavours that don't work with our default image

[databus23]

A tech preview customer selected m1.small and the creation fails with a rather generic error Couldn't create node k8s-pool-test-fqt2v: Invalid request due to incorrect syntax or missing required parameters..
Digging through the nova logs I found Flavor's memory is too small for requested image. We should avoid giving the users a selection that is bound to fail.

We need to decide where we want to fix it, the openstack metadata call or the UI.

[BugRoger]

Hm. Odd. Small used to work

[edda]

I always use small. So far haven't had an issue with it.

[bozinsky]

I have fixed the small image issue. Was caused by a external constraint in openstack. You can close this.

[BugRoger]

We now collect the flavors from Openstack. If the UI picks the flavors from the metadata API, we could filter the list to only return working flavors.

Would also be good to have for custom flavors. Or other Openstacks with different naming schemes...

[BugRoger]

Fixed by #130?

[BugRoger]

Fixed by #130