Added effect for BusLeft BusCenter and BusRight, fixes Bug #1326658
Merge remote-tracking branch 'upstream/master' into bus_effect
switched to LeftBus and Rigt bus in Shade skin
Implement switch type parameters
Create a base class for EffectParameterSlot and EffectButtonParameterSlot to avoid duplicate code
Move updated() signal to EffectParameterSlotBase
Use EffectParameterSlotBasePointer inside WEffectParameter
Display labels for button parameters; also create a base class for WEffectParameter and WEffectButtonParameter to avoid duplicate code
Fix DOM element's name (Parameters --> ButtonParameters)
Set kEffectDebugOutput to false
Do not delete analyzer data if track does not provide valid alternatives
Remove ASCII art from headers
Rename EQ preferences check box and allow the user to modify the frequencies regardless the state of the check box
Use fidlib to create the Bessel filters
Use the new EngineFilterIIR constructor in analyserwaveform.cpp
Make Bessel filters receive frequency changes and fix crackles when frequency corners are changed for EngineFilterButterworth
Remove the hard coded filter coefficients
Some coding style improvements
Do ramping for Bessel filters
Fix crackles when changing frequency corners for High Pass Bessel filter