Attempt to fix cloud-export unzipping failure

Change IFileSystem.unzip to use 7zip command-line under Windows
Note, the path to this must be injected through yok!
Also, update unzip dependencies to 0.1.11 to plug-in other potential issues

refs http://teampulse.telerik.com/view#item/282005
Merge pull request #618 from Icenium/totev/fix-export

Attempt to fix cloud-export unzipping failure