Remove 'using namespace std;' from some headers (#6076)

plugins/Compressor/Compressor.cpp

@@ -328,7 +328,7 @@ bool CompressorEffect::processAudioBuffer(sampleFrame* buf, const fpp_t frames)
 			m_rmsVal[i] = m_rmsTimeConst * m_rmsVal[i] + ((1 - m_rmsTimeConst) * (inputValue * inputValue));
 
 			// Grab the peak or RMS value
-			inputValue = qMax(COMP_NOISE_FLOOR, peakmode ? abs(inputValue) : sqrt(m_rmsVal[i]));
+			inputValue = qMax(COMP_NOISE_FLOOR, peakmode ? std::abs(inputValue) : std::sqrt(m_rmsVal[i]));
 
 			// The following code uses math magic to semi-efficiently
 			// find the largest value in the lookahead buffer.

plugins/GigPlayer/GigPlayer.cpp

@@ -568,7 +568,7 @@ void GigInstrument::loadSample( GigSample& sample, sampleFrame* sampleData, f_cn
 		{
 			samplestoloopend = loopEnd - sample.sample->GetPos();
 			readsamples = sample.sample->Read( &buffer[totalreadsamples * sample.sample->FrameSize],
-					min( samplestoread, samplestoloopend ) );
+					std::min( samplestoread, samplestoloopend ) );
 			samplestoread -= readsamples;
 			totalreadsamples += readsamples;
 

plugins/vestige/vestige.cpp

@@ -137,7 +137,7 @@ public:
 		return m_pluginSubWindow.get();
 	}
 private:
-	unique_ptr<QMdiSubWindow> m_pluginSubWindow;
+	std::unique_ptr<QMdiSubWindow> m_pluginSubWindow;
 };