[MAP] ~25 typo fixes, updated DJ station instruction sheet, replaced missing disposal pipe underneath HoP office door

* Edited arcade.dm: Fixes "Pin ball" typo in arcade machine description
* Edited encryptionkey.dm: Fixes about nineteen typos (#567)
* Edited tools.dm: Fixes "screwwy" typo in screwdriver description
* Edited paper.dm: Updates DJ station instruction sheet due to the removal of the subspace broadcaster and receiver from the DJ station (#638)
* Edited lib_items.dm: Fixes "unrwenched" typo in bookshelf deconstruction step (#527)
* Edited tgstation.2.1.2.dmm: Adds updated DJ station instruction sheet to DJ station, replaces missing disposal pipe underneath HoP office door (#622).