Adding standalone compression workflow

[SkepticRaven]

This adds the effort related to compressing data from one cloud resource and placing it on another.

Rough workflow follows 3 steps:

1. Retrieve video
2. Compress video
3. Push compressed video

[SkepticRaven]

Branch is now ready for review! This is a workflow that we don't plan on supporting indefinitely, but giving it a place to live for future documentation.
@gbeane This is a nice intro to how simpler nextflow workflows can be written (only 3 main steps), since it's a bit less tangled than our main pipeline (50+ steps).