Adjusted the build script behavior

Removed some absolute path, and refactored the code so
it handles the nested folder archives
Removed unused function
Merge branch 'scripts' of https://github.com/bliker/cmder into scripts

Conflicts:
	scripts/build.ps1
In powershell you pretty much never want to use Write-Host, its output can't be redirected along the pipeline. You couldn't pipe this output to a logfile.
Silencing the output from 7z so I can actually see what else the script is
doing.
Adding some clearer dubugging info for cleaning up folders
merging in new additions to the pull request
Merge pull request #162 from Jackbennett/scripts

Minor changes for #152