README: update the Homebrew site address

Thanks @xfq

(cherry-picked from b410b15e8da1a8d285f431640ff165e634196115)

Closes gh-1971

README.md

@@ -25,7 +25,7 @@ In order to build jQuery, you need to have the latest Node.js/npm and git 1.7 or
 
 For Windows, you have to download and install [git](http://git-scm.com/downloads) and [Node.js](http://nodejs.org/download/).
 
-Mac OS users should install [Homebrew](http://mxcl.github.com/homebrew/). Once Homebrew is installed, run `brew install git` to install git,
+Mac OS users should install [Homebrew](http://brew.sh/). Once Homebrew is installed, run `brew install git` to install git,
 and `brew install node` to install Node.js.
 
 Linux/BSD users should use their appropriate package managers to install git and Node.js, or build from source