Merge pull request #4 from MirantisDellCrowbar/feature/pfs/betty/grizzly

venv
swift support for glance
add swift dependency
remove unused options and update glance config to support swift as storage
typo
return default storage to file
Merge pull request #76 from MirantisDellCrowbar/feature/DCB-87/grizzly/master

swift support for glance