Add nsock_scan files to the Windows MSVC project.

git-svn-id: https://svn.nmap.org/nmap-exp/d33tah/nmap-nsock-scan@32627 e0a8ed71-7df4-0310-8962-fdc924857419
Call nsi_delete to close the connection immediately.

git-svn-id: https://svn.nmap.org/nmap-exp/d33tah/nmap-nsock-scan@32629 e0a8ed71-7df4-0310-8962-fdc924857419