Readme install instructions shouldn't be wrong

[RieBi]

In README.md it says that to install carnac using chocolatey you would use cinst carnac That, obviously, didn't work. I used a different command: choco install carnac and it worked. It's good that I remembered how to install with chocolatey, but if not it I wouldn't be able to do it.

Readme needs to be updated. Or if that command is intended for different OS (I'm using windows) or something, it needs to be stated like that. Right now it's somewhat confusing.