added note about PYTHONCASEOK to installation instructions
added note about PYTHONCASEOK to installation instructions

fiuba08/robotframework,fiuba08/robotframework,fiuba08/robotframework,fiuba08/robotframework,ldtri0209/robotframework,ldtri0209/robotframework,waldenner/robotframework,waldenner/robotframework,fiuba08/robotframework,ldtri0209/robotframework,ldtri0209/robotframework,waldenner/robotframework,waldenner/robotframework,waldenner/robotframework,ldtri0209/robotframework