the URL structure for windows binaries provided on the nodejs download site changed between NPM 0.x and 4.x:
additionally we have a hard-coded check on version "2.x" in the code which has to be adapted.
this is a bit more complicated because since v4.0.0 also no more SHA-1 checksum files are provided on the nodejs dist folder. only SHA-256 files. but maven does still only support SHA-1 checksums.
so we have to validated the binary while downloading to the proxy via SHA-256, and generate a new SHA-1 checksum for Maven after this for output.
also added integration tests