Update to bosh cli v2

[jmcarp]

Development on the ruby bosh cli is frozen in favor of bosh-cli. Probably not a high priority, but we should switch scripts that use the old bosh cli to the new one:

• finalize-bosh-release script
• bosh-errand script
• jumpbox script
• bosh-init in bootstrap

Then we can

• delete legacy bosh and bosh-init from task image