Fix issue when a the `preferred_ip` is deallocated from the node.
add vpc support
set connection state ~atomically, preventing race condition in setup threads
add node core and memory amounts in slurm.conf, so we can use select/cons_res
gracefully handle vpcs, subnets with no Name tag
Allow IAM instance profiles to be passed through input configuration, enables association of IAM roles with clusters to avoid passing credentials
add vpc support
set connection state ~atomically, preventing race condition in setup threads
have slurm schedule cores as consumable resources, not just memory
not quite finished support for fetching hostkeys from launched instances
sync with upstream/master
move this to a branch

Revert "not quite finished support for fetching hostkeys from launched instances"

This reverts commit 6b17dd7847b7a58e439311fd58cec08b7b053eb9.
calculate aws key fingerprints the same way aws does
calculate aws key fingerprints the same way aws does
slurmctld will get node core counts, memory amounts from the nodes