• Add project helper functions.
• Add a few defcustom's
• Add ns helper functions.

NOTE: clojure-ts-sort-ns is not implemented, I think we should try to leverage Tree-sitter for that somehow, so I need more time to think about the implementation.

#117

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• You've added tests (if possible) to cover your change(s). Bugfix, indentation, and font-lock tests are extremely important!
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• You've updated the readme (if adding/changing user-visible functionality).

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