More features for organization of env variables

[nbbaier]

As my use of val town has increased, so has the number of env variables I'm managing and, because there is currently no way to filter, sort, or group environment variables once they are defined, it's become hard to sort through them. I'd love to see the following features:

• Notes/more detailed descriptions beyond just names to give more contet
• Custom grouping (for instance, grouping my various AI keys together)
• Search/filtering over env variables