Significantly reduced installation complexity.

Updated gyp scripts to use a packaged, statically linked libcouchbase
rather than forcing the user to deal with having a compatible libcouchbase
installation already available before install couchnode.  Additionally,
npm repository will now be able to ship with prebuild windows binaries.

Change-Id: Ie2f5c2cdeff4f5f86823a6115d69e142e6bbb84c