Add todo group/tag feature

[Or1g3n]

idea 1

• -g command which stands for group
• Sub command --a to add a group and --r to remove a group
• When adding new todos, user can use --g sub command to trigger selecting an available group to categorize todo

potential issues

• Groups would have to be stored. Either the .json would have to be restructured to accommodate (I.e., the json would have nested tables, one that stores todos, other that stores groups
• This can lead to complexity... do we then create key-value pairs when a todo is assigned a group (database style)??

idea 2

• Add a sub command --t to add command that allows user to add one or more tags
• This would allow for more robust fuzzy find when searching todos list and also the ability to sort by tags
• less complex than idea 1 but not as easy to reuse tags