fix(install.sh): accept a version argument and anticipate non-root install
Merge pull request #39 from deis/installer-fixes

fix(install.sh): accept a version argument and anticipate non-root installs
feat(deis-cli): add installer script to pipe into sh

This allows one-liner installs:
curl -sSL http://deis.io/deis-cli/install.sh | sh
Merge pull request #40 from deis/deis-cli-installer

feat(deis-cli): add installer script to pipe into sh
feat(post): deis 0.13 release