Add StreamReaderProtocol to __all__.
Add StreamReaderProtocol to __all__.

1st1/asyncio,manipopopo/asyncio,haypo/trollius,vxgmichel/asyncio,gsb-eng/asyncio,Martiusweb/asyncio,fallen/asyncio,jashandeep-sohi/asyncio,gsb-eng/asyncio,haypo/trollius,jashandeep-sohi/asyncio,Martiusweb/asyncio,manipopopo/asyncio,haypo/trollius,gvanrossum/asyncio,1st1/asyncio,jashandeep-sohi/asyncio,vxgmichel/asyncio,gvanrossum/asyncio,Martiusweb/asyncio,manipopopo/asyncio,ajdavis/asyncio,gsb-eng/asyncio,fallen/asyncio,gvanrossum/asyncio,1st1/asyncio,vxgmichel/asyncio,fallen/asyncio,ajdavis/asyncio,ajdavis/asyncio