Default Endpoints, minor revisions (#477)
Default Endpoints, minor revisions (#477)

* Default Endpoints, minor revisions

A few suggestions towards making the document easier to understand, and also adding the "default endpoint" section.

* Update prebid-1.0-API.md

sonobi/prebid.github.io,prebid/prebid.github.io,prebid/prebid.github.io,sonobi/prebid.github.io,sonobi/prebid.github.io,prebid/prebid.github.io