Zeta Global SSP Analytics Adapter: add docs for new analytics adapter (#3460)
Zeta Global SSP Analytics Adapter: add docs for new analytics adapter (#3460)

* Zeta Global SSP Analytics Adapter: add docs for the new analytics adapter

* Zeta Global SSP Analytics Adapter: improve docs for the new analytics adapter
prebid/prebid.github.io,prebid/prebid.github.io,prebid/prebid.github.io