fixed superglobal name and substr() usage in Request
added $request and $response as global objects

We need to access those objects, for example to access request params,
or set response headers. So the controllers can now declare $request
and $response as global vars to achieve this.
Merge branch 'fixes' into request-enhancements
Added headers management in Request object
Fixed URL fetching in Request

If Bottle is used within document root, the Bottle_Request::_docroot
is / and the uri is an empty string. Now, the uri begins with a / in
any case.
added $request and $response as global objects

We need to access those objects, for example to access request params,
or set response headers. So the controllers can now declare $request
and $response as global vars to achieve this.
fixed headers fetching
Merge branch 'request-enhancements' of github.com:gordon-/php-bottle into request-enhancements

Conflicts:
	bottle/core.php
	bottle/request.php
Added an isAjax method to Request

This method is useful to know if the current request is generated by an XHR
object (thus meaning it’s AJAX). It can be used to change conditionnally the
content of a result.
Merge pull request #10 from gordon-/request-enhancements

Request enhancements