Fixes path issue in Windows exe launchers

Using spaces in Windows is common. This patch fixes an issue in the exe launch
wrappers generated in the "Scripts" directory where unnecessary quoting causes
the following error.

Fatal error in launcher: Unable to create process using '""C:\Program Files (x86)\Cloudbase    Solutions\OpenStack\Nova\Python27\python.exe"" "C:\Program Files (x86)\Cloudbase Solutions\OpenStack\Nova\Python27\Scripts\nova.exe" '

Closes issue: #1997