Route parameters support

Here is some code to add support for route parameters like this:
```
/people/:id
```
As a side effect, regular expressions can be used as URL. However, exact route matches retain a higher priority.

To use the route parameters, pass a function to the endpoint, for example:
```JS
get("/people/:id", function(params) { 
    var id = params.id;
    ...
});
```