Updating for latest chocolatey. 

The latest version of chocolatey(0.9.8.25) has made some changes, they've removed the bat files and replaced them with exes. There is also an environment variable which identifies the installation directory.

I've updated the step templates for chocolatey to work with the latest version.

Updated for the latest chocolatey:
-cinst.exe
-ChocolateyInstall environment variable