Karabiner quit working in Sierra. How do I map my menu/application key to be Command?

Question

I have a microsoft keyboard. When I upgraded to Sierra Karabiner quit working. It was previously mapping my menu/application key to act as pressing the left Command key instead of doing nothing. How can I repair this behavior.

Answer 1

Found the solution here https://github.com/tekezo/Karabiner-Elements/tree/master/usage

Uninstalled existing Karabiner
Installed Karabiner-Elements according to instructions in the link.
Created ~/.karabiner.d/configuration/karabiner.json
With the following JSON inside

{
    "profiles": [
        {
            "name": "Default profile",
            "selected": true,
            "simple_modifications": {
                "application" : "right_command"
            }
        }
    ]
}

Answer 2

For the ones who are not at ease with json files, you can use BetterTouchTool as suggested here

It allows easily adding of keyboard shortcuts but also additional trackpad gestures, with an easy to use GUI.