fix(package): Fix UMD build
fix(package): Fix UMD build

This fixes the UMD build:

1. Now, in a require-less environment, it looks for a "React" global instead of "react" global which was wrong
2. The exported global name is now "redbox" instead of "redbox-react" to match the filename and remove the dash in global

DenisIzmaylov/pinkbox-react,gaearon/redbox-react,commissure/redbox-react,commissure/redbox-react,PixnBits/redbox-react,brenoc/redbox-react,KeywordBrain/redbox-react,mikekidder/redbox-react