docs(CHANGELOG): update for v0.12.0
chore(release): update version to v0.12.0
feat(userdata): add deisctl to the coreos install
Merge pull request #1903 from Xe/feat/userdata/deisctl-in-userdata

feat(userdata): add deisctl to the coreos install
feat(*): Wrap deis run into a pty container

Removes requirements to connect directly to a machine
to receives the output and exit code from deis run