Use new cloud id mapping system

Depends on the corresponding change to python-jiocloud...
Fix cloud layout reference
Direct Vagrant at the correct file
Only specify a mapping file if one is passed in
Use pip trunk and pip-accel for faster jobs
Use sorenh/mapping branch of python-jiocloud
Fail gracefully if $env not set
Use proper upstream python-jiocloud

The mapping branch has been merged now, so it's all good.
fix typo
Merge pull request #130 from bodepd/mappings

Mappings