Fixed build problems related to the symbol redefinitions.

Builds/Linux/Makefile

Builds/MacOSX/open-ephys.xcodeproj/project.pbxproj

Builds/VisualStudio2012/open-ephys.vcxproj

Builds/VisualStudio2013/open-ephys.vcxproj

JuceLibraryCode/JuceHeader.h

PluginGenerator/Builds/LinuxMakefile/Makefile

...acOSX/OpenEphys_PluginGenerator.xcodeproj/project.pbxproj

...Builds/VisualStudio2013/OpenEphys_PluginGenerator.vcxproj

...Builds/VisualStudio2015/OpenEphys_PluginGenerator.vcxproj

PluginGenerator/Projucer.jucer

Source/Plugins/Test/Makefile

Source/Plugins/Test/OpenEphysLib.cpp

Source/Plugins/Test/TestPlugin0706sinkProcessor.cpp

Source/Plugins/Test/TestPlugin0706sinkProcessor.h

Source/Plugins/Test/TestPlugin0706sinkProcessorEditor.cpp

Source/Plugins/Test/TestPlugin0706sinkProcessorEditor.h

Source/Processors/PluginManager/OpenEphysPlugin.h

Source/UI/LookAndFeel/MaterialButtonLookAndFeel.h

Source/UI/LookAndFeel/MaterialSliderLookAndFeel.h

Source/UI/Utils/ButtonGroupManager.h