basic_filters.h: Saner limits for frequency
Do not display ENV/LFO tab in plugin window if controls are disabled in it (SF2 Player and OpulenZ)
Merge https://github.com/LMMS/lmms into bug468
basic_filters.h: Tweaked limits for cutoff.
Merge pull request #492 from diizy/stable-0.4

GraphModel: fix/improve normalize() function - remove bias before maximi...
Merge pull request #494 from diizy/stable-0.4

Desktop file modification to correct ubuntu behavior, icon file copied t...
Removed obsolete pch.h include
AutomatableModel: coding style improvements
AutomatableModel: avoid hiding virtual functions by overload
AutomationPattern: define constants outside class declarations
ControllerView: remove unused member variable
ModelView, Model: coding style improvements
SerializingObject: made saveSettings() and loadSettings() pure virtual

All classes inheriting from SerializingObject should also provide
according functionality, therefore ensure, they implement methods for
loading and saving settings.
Graph: removed unused member variable
ZynAddSubFX: fixed various CLANG compiler warnings
AudioFileProcessor: fixed various CLANG compiler warnings
BitInvader: fixed various CLANG compiler warnings
LB302: fixed various CLANG compiler warnings
OPL2: fixed various CLANG compiler warnings
Papu: fixed various CLANG compiler warnings