Docs: Update walkthrough to better document creating and deleting resources

[jeremyrickard]

Part of #1678

Update the walkthrough to better document creating and removing resources. This could include how to use parameters for creating instances and bindings (this is on a separate page, maybe just link to it).

Should examples only be with Kubectl? Or should we also include svcat?

[carolynvs]

Related #1784

[arschles]

I think we should include svcat as the primary tool where possible

[jeremyrickard]

Create a secondary issue for better documentation of the manifests for the various types. @carolynvs

[carolynvs]

Here's an issue to track documenting the schema: #1825

[jberkhahn]

I feel like this is satisfied by the walkthrough on the doc site, so closing this one.