First pass at unbundle workflows using unbundle pipelines
Merge branch 'bundle-stream' of https://github.com/eucalyptus/euca2ools into bundle-fe

Conflicts:
	euca2ools/bundle/pipes/core.py
Remove old progress method, remove property, edit doc strings for pipe methods
Remove unsed private key path in pipeline, allow None for progressbar
Add progress bar to unbundle
Formatting. Catch NameError if progressbar module not avail.
Update test code to run with multiprocess
Clean up unbundle command and pipeline
Merge branch 'bundle-stream' of https://github.com/eucalyptus/euca2ools into bundle-fe

Conflicts:
	euca2ools/bundle/pipes/core.py
Fix Manifest image_size attr. Use mixins for progress bar.
Clean up unbundle. Move methods to utils and fittings from core.
Allow unbundle to output to stdout. Some initial clean up debug logging
Handle keyboard interrupt
Add comments
Close all subprocesses if exception in unbundle pipe. Allow maxbytes to be set for unbundle pipe.
First pass at allowing unbundle to access a remote image via walrus request
Clean up and format
Replace StringIO with pipe for fetching remote manifest
Create unbunbdle stream (stdin/out) command for use with unbundle pipe
Unbundle stream comments and clean up