Added resource_spawner/spawn_resources.bin to gitignore

This file is not required to be pushed as it is generated by running makebin.sh
Moved configuring contrail VM on top of the fab task list

This is only required when using contrail golden image - due to some stale data in it
contrail takes time to boot up and causing errors while creating overcloud resources.
Removed Hardcoded ssh keys

ssh keys which was hardcoded has been removed.
This was required to move the code to public git.
Merge pull request #3 from hkumarmk/make_it_configurable

Removed Hardcoded ssh keys