removed unused error and exception handling
Merge branch '3.3/develop' into 3.3/feature/17-restful-error-handling
added RESTful_HTTP_Exception class stub
imported response() method from Kohana::Exception for modification
removed unnecessary $http_header_status variable
if things go wrong error message is displayed only in DEV environment
Exception response body is now generated by RESTful_Response::render() and the default RESTful_Response::$_default_type
when in DEV env additional debug details are provided
Merge branch '3.3/feature/17-restful-error-handling' into 3.3/develop
replaced all HTTP_Exceptions with RESTful_HTTP_Exceptions
Fixed the way exceptions are handled, so standard HTTP_Exceptions work as usual, while RESTful_HTTP_Exceptions are handled by the module

closes #17
Merge branch '3.3/feature/17-restful-error-handling' into 3.3/develop