UTI registrations are wrong

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Describe the bug
The registration of UTIs in Info.plist is done wrong. This messes up the launch services database for the users, which can lead to all kind of problems when handling files, not just in MacVim, but any app that may need to handle any of the types declared by MacVim. In particular, the Exported Types should only contain custom types owned by MacVim. All third party types and built in types should only be declared as Imported Types. Otherwise MacVim takes ownership of them, overruling the true owners of the type, which is extremely rude. In fact, standard built-in types should not be declared at all, in particular types starting with public. What is worse, MacVim declares some types with errors. In particular, com.adobe.postscript is declared as inheriting from public.plain-text. This is absolutely wrong, as PostScript it is not plain text. It only inherits from public.data. This makes the postscript type unusable for any app that wants to use the type, and breaks the system of your users.

Environment (please complete the following information):

• Vim version 8.2.2156

Additional context
Add any other context about the problem here.

Inspect the Info.plist UTI declarations first, separating MacVim-owned custom types from third-party and built-in types. Correct the com.adobe.postscript inheritance and remove standard public.* declarations; the work is done when exported, imported, and inherited types match the ownership and inheritance requirements described in the issue.