chore(gateapi): update gate api to 1.20 (spinnaker#250)

Co-authored-by: Pere Kyle <[email protected]>

chore(gateapi): Update gate api to 1.18.0 (spinnaker#237)

chore(gateapi): Update gate api to 1.17.0 (spinnaker#229) (spinnaker#230

)

chore(gateapi): Update gate api for 1.16.1 (spinnaker#218)

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)