Not much to really say about it. I just got tired of yellowish-green grass, so I took it upon myself to fix it. It makes the game look twenty times better in my opinion. I'm not really attached to it, I just felt like sharing with the rest of the community.
That's about it, just look at the screenshots for an idea of what it does.
The extreme hills after screenshot I just realized has "plains" as the biome in the corner- that's because the screenshot is taken on the border looking at the extreme hills biome.