Just a few days after Google’s Nest knocked $100 off its Nest Secure bundle, bringing it down to $400, Amazon-owned Ring launched its own equivalent – the $200 Ring Alarm kit. The two leaders are now going to start slugging it out, and Amazon seems to have notched up a decisive win outside the home – in a deal with Marriott Hotels to use Alexa throughout its hospitality business. Nest has always been one of the more expensive brands on the market, but the Ring Alarm kit is now 50% cheaper. It is not clear if Amazon is selling these at a loss to boost share, which could be reclaimed later through its retail operations, but Nest has consistently performed…