How to add black Edge to a Mesh/Decor

Hi,

The textures I use is from the software “MagicaVoxel”, and this is simple colours.
So, with the Direction light, all textures are a little bit glowing and sometimes I can’t make the difference if it is plane or with with perspective.

this pitcure is from MagicaVoxel for the exemple

And what I would like to do is something like this:

or if you want a better exemple, it is something like the game “Trove”

If you’re using Unity 5, you can import the Image Effects package and look at the Edge Detection scripts.

How do you use the Edge Detection Script, I tried adding it to an object whose edges I wanted to be outlined but it simply says I can’t add the script because it is an editor script?