refactored debug output. Now all is set by using `verbose = true` in the config file instead of manually uncommenting code.
Also moved to platform independent code, from Windows only
Merge pull request #192 from Tieske/debug_output

Improved debug/verbose output
If PowerShell is not available, a proper message is now displayed when installing on Windows without admin priviledges
Merge pull request #193 from Tieske/no_powershell

Windows; remove powershell requirement