Several APIs support options that can be specified as a query parameter or a
request body parameter.
Currently, this is documented using notes, which can get rather lengthy. This
replaces those multiple notes with a single note and a footnote.
Changes:
* Adds API reference docs for the delete snapshot repo API.
* Corrects an error in the delete snapshot repo API spec. Comma-separated
repository names are not supported.
* Relocates the existing delete snapshot repo API example docs.
