Alpha release for test usage only (v0.4.32-alpha)

Thanks to @chirs241097 , added pitchbend support for vst2 plugins.
Since the wrapper of vst3 do not support PitchBend currently, we can support that for only vst2.

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感谢 @chirs241097 增加了对Pitch Bend 的支持。
由于WDL的封装尚未实现对vst3支持PitchBend信号，目前只能先去支持vst2了。