Added nbt_storage() scapet function (#655)

* Added storage() scarpet function

Allows you to easly manage vanilla data command storage

* Added docs and uniformed with scoreboard()

storage(key, nbt) will now return the previous value to be consistant with the scoreboard() command.

* Included imports

* Renamed storage function to nbt_storage

* Update docs/scarpet/api/Auxiliary.md

Co-authored-by: gnembon <41132274+gnembon@users.noreply.github.com>

docs/scarpet/resources/editors/npp/scarpet.xml

@@ -86,6 +86,8 @@
 
                 load_app_data store_app_data read_file write_file delete_file list_files
                 escape_nbt parse_nbt encode_nbt tag_matches statistic
+
+                nbt_storage
             </Keywords>
             <Keywords name="Keywords3">euler pi null true false</Keywords>
             <Keywords name="Keywords4">x y z p</Keywords>