Updated ReleaseNotes file for alpha 3 release.
Updated ReleaseNotes file for alpha 3 release.

swinman/pyusb,AlanJAS/pyusb,kopchik/pyusb,kopchik/pyusb,swinman/pyusb,makerbot/pyusb,AlanJAS/pyusb,rabryan/pyusb,h3nj3/pyusb,rabryan/pyusb,h3nj3/pyusb,makerbot/pyusb,karlp/pyusb,karlp/pyusb