Fixed the documentation and the installation bash script to reflect the 301 redirect from npmjs.org to www.npmjs.org

Passing the curl output to sh was failing since the output was an HTML from a 301 redirect, since npmjs.org is redirecting to www.npmjs.org, therefore I changed the places where this was happening or mentioned.
adds static 404 page for docs
Minor tweaks to paths in the documentation 404 file.
includes all .DS_Store in .gitignore
adds .DS_Store to .gitignore
email addresses are special (fixes #646)