Support normalizeHttpPath

This options should probably become the default at some point (opt-out
instead of opt-in).

Thoughts on setting this globally (config.json) are welcome.

Mandatory PR: https://github.com/strongloop/strong-remoting/pull/90
A nice to have feature: allow developers to turn on/off  the flag `normalizeHttpPath` via `server/config.json`.

```js
options = extend(this.get('remoting') || {}, options);
var remotes = this.remotes();
var handler = this._handlers[type] = remotes.handler(type, options);
```

Usage in `config.json`:

```json
{
  "port": 3000,
  "restApiRoot": "/api",
  "remoting": {
    "normalizeHttpPath": true
  }
}
```

@ritch @raymondfeng thoughts?
@fabien it's ok to leave this feature out of scope of this PR.