Comment 1 for bug 1519953

I have already updated this one : https://github.com/mixxxdj/mixxx/pull/590

I have also corrected HID mapping : https://github.com/mixxxdj/mixxx/pull/667

Effects CO:
Switched flanger to [QuickEffectRack1_[ChannelX]],super1

EQ CO:
Switched low/mid/high to [EqualizerRack1_[ChannelX]_Effect1], parameter1/2/3
Switched filter to [EqualizerRack1_X_Effect1], control

Sync button:
Added sync_enabled on "tempo" button
Sync button is "beatsync"
Added led logic to tempo button:
- off -> sync_enabled==0
- on -> sync_enabled==1
- code commented out to blink when "master" (see comment in the file

4-deck support added

see also updated wiki page: http://www.mixxx.org/wiki/doku.php/hercules_dj_control_mp3_e2