Make devstack release Vagrantfile use aspen-rc1 box if requested
Add comment about openedx_releases hash
Merge pull request #1623 from edx/openedx-release-aspen-rc-box-file

Make devstack release Vagrantfile use aspen-rc1 box if requested
Make fullstack release Vagrantfile use aspen-rc1 box if requested
Merge pull request #1626 from edx/openedx-release-aspen-rc-box-file

Make fullstack release Vagrantfile use aspen-rc1 box if requested