Update analytics.md (#1523)
Update analytics.md (#1523)

Change Cost of RealVu Analytics Adapter from "Free" to "Contact vendor"
sonobi/prebid.github.io,prebid/prebid.github.io,prebid/prebid.github.io,sonobi/prebid.github.io,prebid/prebid.github.io,sonobi/prebid.github.io