Add miniedit recipe

* recipes/miniedit: New recipe: Enhanced editing for minibuffer fields

I don't maintain the package, I just find it really handy for editing things like M-: (eval-expression), replace-regexp, etc. I've installed it locally, replaced my manually-downloaded .el with it, and tested that it continues to work.

Package repository: https://github.com/emacsmirror/miniedit