Unify injected print-method implementations with orchard.print

[alexander-yakushev]

Now that orchard.print has more printers for different classes, we can use it instead of custom code in cider-nrepl to modify print-method behavior. Brings more consistency and removes some code too.

One controversial change: different derefables like atoms, futures, etc., have changed how they look:

;; before
#atom[{:status :ready, :val 1} 0x11381415]
#promise[{:status :pending, :val nil} 0x2a40ec4d]
#delay[{:status :failed, :val #error {....}]

;; now
#atom[1]
#promise[<pending>]
#delay[<failed> #error[...]]

I hope this doesn't break anything – if people rely on printed representation of these objects, specifically on how cider-nrepl augments them, and then parse that, they are probably in a bigger trouble already.

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