Got rid of the `available` column in model.Headnode
Got rid of the `available` column in model.Headnode

This isn't actually used.

lokI8/haas,henn/hil_sahil,henn/hil_sahil,kylehogan/haas,kylehogan/hil,henn/haas,kylehogan/hil,apoorvemohan/haas,meng-sun/hil,henn/hil,SahilTikale/switchHaaS,CCI-MOC/haas,henn/hil,apoorvemohan/haas,meng-sun/hil,SahilTikale/haas