fix(folders): Alphabetical folder order should be case insensitive.

[ff7762]

This PR is a fix for the order of folders in this issue #1286

Below in the screenshot, you can see the current functionality of this issue, which matches the fix that was described in the ticket.

Below is the functionality before my changes

You can see that the folders are now sorted in the way the ticket describes.

I have also written a test for this, to ensure maintainability of this functionality.

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Questions about feature/bug bounties.
(Haven't seen another channel for correspondence.)

This is my first contribution as part of the feature bounty program. It wasn't marked as suitable for starters but I wanted to give it a shot. I hope this is useful for the users.

Is there a communications channel where payments are coordinated for accepted solutions?
Also, does high priority = Bronze tier reward? This task doesn't fit in the iron reward because that's medium and below priority.

Let me know if there are any issues, I will fix them asap.

[castaway]

Looks like a good fix, just need to tweak the tests to be slightly more clever, thanks!

[castaway]

Please don't submit the changelog in a PR, as we generate those on deploy

[castaway]

The built-in sort() for the folder list is putting the inbox etc last, so you'll need to rethink the test