Added an option to ignore www subdomains (instead of redirecting)

[jeddawson]

Added an optional ignoreWWW parameter. When enabled, subdomain will ignore www subdomains without removing them and redirecting.

My use case for this is a web app that dynamically handles customer subdomains and routes www traffic.

Here's an example:

app.use(subdomain({base: 'basedomain.tld', ignoreWWW: true}));
app.get('/subdomain/:subdomain/', function(req,res,next){
     console.log(req.params.subdomain);
     //do something based on the subdomain
     next();
});
app.get('/', function(req,res,next){
   // either the base domain, or www subdomain
   next(); 
});

[edwardhotchkiss]

Awesome @jeddawson: published.

[jeddawson]

Thanks @edwardhotchkiss. If you'd like me to update the example in the readme or just add more info, I'd be happy to contribute to that as well.

[edwardhotchkiss]

@jeddawson that would be awesome, thanks!