Minor tweaks to -isEqual: and -hash in MIKMIDIEndpointSynthesizerInstrument.
Minor tweaks to -isEqual: and -hash in MIKMIDIEndpointSynthesizerInstrument.

bamboostick/MIKMIDI,bamboostick/MIKMIDI,alessandrostone/MIKMIDI,bamboostick/MIKMIDI,alessandrostone/MIKMIDI,alessandrostone/MIKMIDI