I...you're trolling, right?
Are any of you even reading the articles or reviews before posting here?
It's been said dozens of times already, but I'll say it again for you. Only this time in bold.
Gatekeeper has three, 3, as in 1, 2, 3, settings. One of the settings completely turns it off, meaning you can install whatever the hell you want.
Now, if Mr. Newbie didn't read the first time, he surely won't understand that whole bold-lettering thing.