AutoDiscover basePath

AutoDiscover basePath by default so if it's not specified AltoRouter will discover it automatically. 

so basically you will no longer need to include 

```php
$router->setBasePath('/AltoRouter/examples/basic');
```
This is safe since its backwards compatible, meaning that if someone specified the baseBath the AltoRouter will still use that! 

I think its much better to try and discover the basePath since less configuration is needed to use AltoRouter and also this makes it more portable since if you move a script based on AltoRouter from FolderA to FolderB then it will work with no changes! 

This is of course not bullet proof since it relies on server SCRIPT_FILENAME and DOCUMENT_ROOT to discover the basePath and I am not sure if these differ in environment other than apache that i tried this.