fix(client): Reverts Gate liveness check. (spinnaker#178)

The Gate liveness check needs rethought since it doesn't
handle authentication cases and is breaking for forwarded ports.
Reverting for now.

fix(gateapi): close body after http.Get to avoid leaking resources (s…

…pinnaker#168) (spinnaker#170)

fix(gateclient): Exits gracefully if Gate server not reachable. (spin…

…naker#152) (spinnaker#157)

 fix(pipeline-template): Update pipeline template commands for API. (s…

…pinnaker#145)

* chore(gateapi): Regenerates Gate API surface.

* fix(pipeline-template): Update pipeline template commands for API.

Merge pull request spinnaker#139 from spinnaker/auto-cherry-pick-1.12…

…-889bce1a6bea90cc31c36728862bb00030705db7

fix(pipeline/exec): Output one pipeline execution after exec. (spinnaker#130)

fix(pipeline/save): Fix setting pipeline type. (spinnaker#129) (spinn…

…aker#131)

fix(iap): Support optional config parameter IapIdToken. (spinnaker#127)

* feat(iap): Support optional config parameter IapIdToken.

* fix(iap): Clear err variable after printing link.

fix(app): Fixes specifying apps with flags only. (spinnaker#114)

Previously the command would fail if there was no file
input from either a flag or STDIN, which was a regression.

fix(pipeline-templates): Update plan command for change in v2 template (

spinnaker#100)

Orca handling.

fix(oauth2): Fixes API calls using OAuth2. (spinnaker#86)

Gate calls were subtly broken due to OAuth2 redirects.
GET calls were traversing the redirects fine, but POST
calls would be turned into GETs with no body, which
the Gate Controllers fail on. Now, when we resolve the
oauth2 token we immediately establish a session for the life
of the spin command so all calls are authenticated.