Fix pythran include path for numpy math functions

Plus Start filling unit test cases

Cython/Compiler/Pythran.py

@@ -201,7 +201,7 @@ def is_pythran_buffer(type_):
 
 def pythran_get_func_include_file(func):
     func = np_func_to_list(func)
-    return "pythonic/include/numpy/%s.hpp" % "/".join(func)
+    return "pythonic/numpy/%s.hpp" % "/".join(func)
 
 def include_pythran_generic(env):
     # Generic files

tests/run/numpy_pythran_unit.pyx

+# mode: run
+# tag: pythran, numpy, cpp
+# cython: np_pythran=True
+
+import numpy as np
+cimport numpy as np
+
+def trigo(np.ndarray[double, ndim=1] angles):
+
+    """
+    >>> a = np.array([0., np.pi, np.pi *2])
+    >>> trigo(a)
+    array([ 1., -1.,  1.])
+    """
+    return np.cos(angles)