add culomb file for backwards compatability

Author: HelgeGehring

femwell/culomb.py

@@ -0,0 +1,12 @@
+import datetime
+import warnings
+
+if datetime.date.today().year <= 2023:
+    warnings.warn(
+        "Typo corrected, femwell.culomb is now called femwell.coulomb. Importing culomb will stop working after the end of 2023",
+        DeprecationWarning,
+    )
+else:
+    raise FileNotFoundError("femwell.culomb will be removed. use femwell.coulomb instead.")
+
+from femwell.coulomb import *