Resolve "Load/Save SFG to file"

Basic serializer for our datastructures to save and load to and from files. Uses a new package called dill that is based on pickle since pickle doesn't support serializing for lambda functions among other types.

Closes #66 (closed)

b_asic/utils.py

@@ -51,6 +51,6 @@ def load_structure(_path: str) -> AbstractOperation:
         with open(_path, "rb") as handle:
             return dill.load(handle)
     except Exception as e:
-        print("Unexpected error occured while saving structure: ", e)
+        print("Unexpected error occured while loading structure: ", e)
     
     return None