Add flow control to differentiate AppD version >=6.1 from the older versions for url composition of the imported solution.

Testing Done: tested on the forked repository with Sharepoint (Standalone) BP solution.
http://yjshi.github.io/yj-solutions-import-6/exportimport-deploy/appdir/docs/index.html?uname=vmware-applicationdirector&repo=solutions-import-6&branch=MS-Sharepoint-2010-BP-v1.0.0