anchor: Source:setEffect
  Applies an audio effect to the Source.
  
  The effect must have been previously defined using love.audio.setEffect.
  success = Source:setEffect( name, enable )
  name string The name of the effect previously set up with love.audio.setEffect.
  enable (true) boolean If false and the given effect name was previously enabled on this Source, disables the effect.
  success boolean Whether the effect was successfully applied to this Source.
  success = Source:setEffect( name, filtersettings )
  name string The name of the effect previously set up with love.audio.setEffect.
  filtersettings table The filter settings to apply prior to the effect, with the following fields:
  filtersettings.type FilterType The type of filter to use.
  filtersettings.volume number The overall volume of the audio. Must be between 0 and 1.
  filtersettings.highgain number Volume of high-frequency audio. Only applies to low-pass and band-pass filters. Must be between 0 and 1.
  filtersettings.lowgain number Volume of low-frequency audio. Only applies to high-pass and band-pass filters. Must be between 0 and 1.
  success boolean Whether the effect and filter were successfully applied to this Source.