Report ad playback metrics

[strangesource]

Problem

The current integration does not report any ad playback metrics to the ConvivaAdAnalytics.

Changes

• Use ConvivaExperienceAnalytics.ICallback to report playhead during ads
• When transitioning playback state during an active ad, report state change to ConvivaAdAnalytics
• On ad start, report RESOLUTION and BITRATE depending on availability

📚 Related PR's

• 📗 #62
• 📙 #63
• 📒 #64