Introduce the bid session and memory management policy of the Prebid SDK

[YuriyVelichkoPI]

Motivation

• Publishers: needs to understand the life cycle and memory management of the ad units and ad views to integrate the Prebid SDK most efficiently and reliably.
• Prebid SDK developers should have the specification of memory management and session handling to follow when introducing the new features or supporting the current ones

Objectives

• Review the bid session flow in Prebid SDK iOS and Android
• Prepare the spec describing the current state of things
• Discuss the paper with the community to develop a single solid specification
• Once the community reviews the specification - introduce changes in the SDKs to follow
• Publish the spec in the public docs

[jsligh]

@YuriyVelichkoPI is this still relevant?