typo fix following code review.

doc/tutorial/extending_theano.txt

@@ -421,7 +421,7 @@ as_op
 as_op is a python decorator that converts a python function into a
 basic Theano op that will call the supplied function during execution.
 
-This isn't the recommand way way to build an op, but allow quick
+This isn't the recommended way to build an op, but allows for a quick
 implementation.
 
 It takes an optional :func:`infer_shape` parameter that must have this

theano/sandbox/cuda/cuda_ndarray.cuh

@@ -450,7 +450,8 @@ static PyObject *CudaNdarray_NewDims(int nd, const inttype * dims)
             return NULL;
         }
     }else{
-        PyErr_SetString(PyExc_MemoryError, "Failed to the CudaNdarray structure.");
+        PyErr_SetString(PyExc_MemoryError,
+                        "Failed to allocate the CudaNdarray structure.");
     }
     return (PyObject*)rval;
 }