add decrypted storage

[nikooo777]

this adds a new requirement for running the player:

• a mysql server is required to handle cache management

Improvements:

• non transcoded content is only decrypted once and then stored as such (less CPU intensive)
• cache recency persists across reboots
• less overhead/faster delivery speeds

[nikooo777]

fixed the damn tests, time to put this in master as it's been running in prod for months now