Added descriptions to processor source code

Source/Processors/AudioNode.h

Source/Processors/DataThreads/DataThread.h

Source/Processors/DataThreads/FPGAThread.h

Source/Processors/DataThreads/FileReaderThread.h

Source/Processors/DataThreads/IntanThread.h

Source/Processors/DataThreads/NetworkThread.h

Source/Processors/DisplayNode.h

Source/Processors/EventNode.h

Source/Processors/FileReader.h

Source/Processors/FilterNode.h

Source/Processors/GenericProcessor.h

Source/Processors/LfpDisplayNode.h

Source/Processors/RecordNode.h

Source/Processors/ResamplingNode.h

Source/Processors/SignalGenerator.h

Source/Processors/SourceNode.h

Source/Processors/SpikeDetector.h

Source/Processors/WiFiOutput.h