Enhance the Audio Recorder

[joggienl]

Enhance the MediaRecorder to expose more analytical information like Volume, RMS and power.

This information can be used in use cases like:

• To create a volume meter
• To detect audio problems (distorted audio, low volume, background noise, etc)

Tasks:

• Enable plugins to be loaded on the recorder (Enhance recorder #341)
• Add an Amplitude plugin (Enhance recorder #341)
• Add an Analyser plugin
• Add a way to detect audio problems based on the previous plugins