Comment 8 for bug 1081701

Here is a description what it will take to implement solution 2, broken down into individual tasks:

Once a) is done, all the other tasks can be done independently.

a) add a new colum on nodegroup to store the maas_url as seen by the cluster

b) have the cluster send that maas_url when cluster starts up, populate the new column on nodegroup

c) change the preseeds:
c1) update absolute_reverse to make it accept another base that will be used in lieu of MAAS_DEFAULT_URL
c2) use the value stored in nodegroup.maas_url in the preseed (use the method 'absolute_reverse' as modified above to generate the proper urls)

d) update the UI: the enlistement preseed is now node-specific: put the link to it on the node page (it currently resides on the node listing page). (Note that change in the preseeds themselves will be tackled in c))

e) use the value stored in nodegroup.maas_url when generating the dhcp config (bug 1081696)