Add ability to include targets file for local experiments #167

After #166 we can use the new launch script or launch GUI to launch a local experiment.

It'd be nice to still be able to specify a separate targets file for local experiments (which would just get merged with the init.yaml dict rather than uploaded). Maybe there could be a checkbox for "upload targets" and the AWS information is only necessary if that box is checked?

This way the init.yaml files for local and example experiments would be identical.