Iot snippets (#477)
Iot snippets (#477)

* Consistency in snippets.

* Cleans up snippets and adds missing registry management snippets

* Fixes style

JustinBeckwith/nodejs-docs-samples,GoogleCloudPlatform/nodejs-docs-samples,GoogleCloudPlatform/nodejs-docs-samples,GoogleCloudPlatform/nodejs-docs-samples,JustinBeckwith/nodejs-docs-samples,JustinBeckwith/nodejs-docs-samples,GoogleCloudPlatform/nodejs-docs-samples