Update/fix aws scripts to run experiments

[sbellem]

Some parts of the aws scripts are slightly outdated such that attempted to run the experiments via aws/run-on-ec2.py fails (e.g.: #419).

Some things to fix:

• hbavss_light and hbavss_batch have changed location and some imports need to be modified.
• Get ipc to work.
• Get powermixing app to work.
• Get butterfly_network app to work.

The main reason for solving these problems is to be able to point others to a working version in order to help them re-run some experiments on their own, or to explore whatever they wish from a working basis.