Merge pull request #356 from esc/vh/enhance/numpy_dtype

Enhance cython defintion of the Numpy dtype

Cython/Includes/numpy/__init__.pxd

@@ -154,12 +154,15 @@ cdef extern from "numpy/arrayobject.h":
 
     ctypedef class numpy.dtype [object PyArray_Descr]:
         # Use PyDataType_* macros when possible, however there are no macros
-        # for accessing some of the fields, so some are defined. Please
-        # ask on cython-dev if you need more.
+        # for accessing some of the fields, so some are defined.
+        cdef char kind
+        cdef char type
+        cdef char byteorder
+        cdef char flags
         cdef int type_num
         cdef int itemsize "elsize"
-        cdef char byteorder
-        cdef object fields
+        cdef int alignment
+        cdef dict fields
         cdef tuple names
 
     ctypedef extern class numpy.flatiter [object PyArrayIterObject]: