Listkeeper: Update Collections and Items without deleting/remaking them

[spark-c]

Currently, in order to change the spelling or content of any list name / description, or item name / note, the thing must be deleted and remade.

Users should be able to use something like
!updatelist [-l <list-name>] [-name <new-name>] [-description <new-description>]
!updateitem [-l <list-name>] <item-name> [-name <new-name>] [-description <new-description>]
in order to update these values.

NOTE: While items have "note" property in the code, we should probably call them "descriptions" here for user ease-of-use. It may be best to update implementation in the future to simply use "description" in the codebase for everything (not use "note").

In order to resolve this issue, (two) functions will need filled out in cogs/Listkeeper.py to receive, and parse user input; (two) functions will also need filled out in cogs/listkeeper_db/lkdb.py to handle interactions with the database using those inputs.