Merge branch 'FastCCD-parallel-backend' into 'master'

Using joblib instead of multiprocessing

See merge request !61

FastCCD.py

-import multiprocessing
+from joblib import Parallel, delayed, parallel_backend
 from time import strftime
 import tempfile
 import shutil
@@ -321,8 +321,10 @@ class FastCCD:
         timestamp = strftime('%X')
         print(f'start time: {timestamp}')
                                       
-        with multiprocessing.Pool(self.Nworker) as pool:
-            res = list(tqdm(pool.imap(process_one_module, jobs), total=len(self.h5list)))
+        with parallel_backend('threading', n_jobs=self.Nworker):
+            res = Parallel( verbose=20)(
+                delayed(process_one_module)(job) for job in tqdm(jobs)
+            )
         
         print('finished:', strftime('%X'))