Bump BOSH director and other gems
Add `bosh_common` and `blobstore_client` to the Gemfile to use gems on Github

To avoid an error in `bundle install`.
Add installing bundler for rvmsudo
Fix gen-stemcell to support new stemcell-builder

Change gen-stemcell to use StageRunnder because build_from_spec.sh was removed from
bosh.
https://github.com/cloudfoundry/bosh/commit/34b4ca5d5350f461a0e413c9416aa3b7135a8542
Merge pull request #19 from jacopen/master

Fix gen-stemcell to support new stemcell-builder
Bump BOSH
Bump BOSH and use DummyPlatform
Bump Bosh and fix `Bosh::Agent::Config` override
Bosh renamed director to bosh-director
Merge pull request #22 from fraenkel/director

Rename director to bosh-director and update Gemfile.lock
Add mode for returning selected release file
Add mode for display only selected release version
Delay retrieving IP address for -m mode
Bump BOSH
Add linux-image-extra-virtual for precise
Bump BOSH
Use `let` to create objects
Use published BOSH gems
Change host's network mask to 16
Fix Travis configuration