fix macOS build (following Projucer changes made in Windows, which removed /Applications/JUCE/modules from its headers). move JUCE headers under source control, so that Windows and macOS can both build against same version of JUCE. remove AUv3 target (I think it's an iOS thing, so it will never work with this macOS fluidsynth dylib).

modules/juce_audio_formats/codecs/juce_LAMEEncoderAudioFormat.h

@@ -0,0 +1,80 @@
+/*
+  ==============================================================================
+
+   This file is part of the JUCE library.
+   Copyright (c) 2017 - ROLI Ltd.
+
+   JUCE is an open source library subject to commercial or open-source
+   licensing.
+
+   By using JUCE, you agree to the terms of both the JUCE 5 End-User License
+   Agreement and JUCE 5 Privacy Policy (both updated and effective as of the
+   27th April 2017).
+
+   End User License Agreement: www.juce.com/juce-5-licence
+   Privacy Policy: www.juce.com/juce-5-privacy-policy
+
+   Or: You may also use this code under the terms of the GPL v3 (see
+   www.gnu.org/licenses).
+
+   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
+   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
+   DISCLAIMED.
+
+  ==============================================================================
+*/
+
+namespace juce
+{
+
+#if JUCE_USE_LAME_AUDIO_FORMAT || defined (DOXYGEN)
+
+//==============================================================================
+/**
+    An AudioFormat class which can use an installed version of the LAME mp3
+    encoder to encode a file.
+
+    This format can't read MP3s, it just writes them. Internally, the
+    AudioFormatWriter object that is returned writes the incoming audio data
+    to a temporary WAV file, and then when the writer is deleted, it invokes
+    the LAME executable to convert the data to an MP3, whose data is then
+    piped into the original OutputStream that was used when first creating
+    the writer.
+
+    @see AudioFormat
+
+    @tags{Audio}
+*/
+class JUCE_API  LAMEEncoderAudioFormat    : public AudioFormat
+{
+public:
+    /** Creates a LAMEEncoderAudioFormat that expects to find a working LAME
+        executable at the location given.
+    */
+    LAMEEncoderAudioFormat (const File& lameExecutableToUse);
+    ~LAMEEncoderAudioFormat();
+
+    bool canHandleFile (const File&);
+    Array<int> getPossibleSampleRates();
+    Array<int> getPossibleBitDepths();
+    bool canDoStereo();
+    bool canDoMono();
+    bool isCompressed();
+    StringArray getQualityOptions();
+
+    AudioFormatReader* createReaderFor (InputStream*, bool deleteStreamIfOpeningFails);
+
+    AudioFormatWriter* createWriterFor (OutputStream*, double sampleRateToUse,
+                                        unsigned int numberOfChannels, int bitsPerSample,
+                                        const StringPairArray& metadataValues, int qualityOptionIndex);
+
+private:
+    File lameApp;
+    class Writer;
+
+    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (LAMEEncoderAudioFormat)
+};
+
+#endif
+
+} // namespace juce