Create general autofill table and category util functions. Update table class to have get categories function.

classes/table.py

@@ -123,6 +123,16 @@ class Table:
         if category.name not in self._categories_map:
             self._categories_map[category.name] = category
 
+    def get_categories(self) -> dict:
+        """
+        Getter for dict of category names and categories.
+
+        Returns:
+            dict: Dictionary consisting of Category names and Category objects.
+        """
+        # I don't know if this is const data. Don't want to allow data to be written as a result of this function.
+        return self._categories_map
+
     def get_category(self, category_name: str) -> Category:
         """
         Getter for specific category. Returns None if not found.