add possibility to install chocolatey also

Module should install chocolatey also:
- added init class
- added the ps1 file as a template
- depends on joshcooper/powershell

Can use either "windows" or 7zip as methods to extract the software
Sure, sorry that was bit vague. I just noticed that the Exec['install chocolatey'] resource is declaring it creates c:\\Chocolatey. 

I was wondering whether it would be a good idea to change this to respect the 'ChocolateyInstall' env var so that it can be installed in an alternate location, if it doesn't already, as per https://github.com/chocolatey/chocolatey/wiki/Installation#before-you-install.

How you would do this I'm not to sure, whether it's best practice to reference env vars inline - generally bad from an OOP point of view - or pass the env var to the chocolatey class - my personal preference.

Does that clarify things?