add in k vector tests (#157)

* add in k vector tests

* rename for pytest

pytest wants names beginning with test_

* fix kvec test

* fix the test issue

* convert k-vec cython import to relative

* convert k-vec cython import to relative as per #157

* add more error detail, skip pytest failure due to problem in seekpath module

* update tests and tested locally

* change tolerance

---------

Co-authored-by: Brian Toby <[email protected]>
Co-authored-by: BHT <[email protected]>

Author: Kvieta1990

GSASII/k_vector_search.py

@@ -27,20 +27,25 @@
 # acknowledged for their useful comments.
 # +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 #
-import numpy as np
 import sys
-from scipy.optimize import linear_sum_assignment
+import time
 import math
+import numpy as np
+from scipy.optimize import linear_sum_assignment
 from . import GSASIIfiles as G2fil
+
+gen_option_avail = True
 try:
     import seekpath
-    from kvec_general import parallel_proc
-    gen_option_avail = True
 except ModuleNotFoundError:
     G2fil.NeededPackage({'magnetic k-vector search':['seekpath']})
+    print('k_vector_search: seekpath could not be imported')
+    gen_option_avail = False
+try:
+    from GSASII.kvec_general import parallel_proc
+except ModuleNotFoundError:
+    print('k_vector_search: kvec_general could not be imported')
     gen_option_avail = False
-import time
-
 
 def unique_id_gen(string_list: list) -> list:
     """Generate unique IDs for strings included in the string list and the same