On: PowerShell is open sourced and is available on Lin...

[jdmichal]

The official cmdlet documentation is versioned, though for some reason it only seems to have versions 3, 4, and 5. Which, agreed is very annoying, since Windows 7 has version 2 by default.

https://technet.microsoft.com/en-us/library/hh849971.aspx

(You should upgrade to at least 3. It has all sorts of useful stuff added! File hashing and web requests at the very least.)