nvim: stop using after

rationale: https://vi.stackexchange.com/a/12735

.config/nvim/after/plugin/oil.lua

@@ -1,34 +0,0 @@
-require("oil").setup {
-    -- This bug would prevent downloading language files from working
-    -- https://github.com/stevearc/oil.nvim/issues/483
-    default_file_explorer = false,
-    columns = {
-        -- "icon",
-        -- "permissions",
-        -- "size",
-        -- "mtime",
-    },
-    skip_confirm_for_simple_edits = true,
-    prompt_save_on_select_new_entry = false,
-    keymaps = {
-        ["g?"] = "actions.show_help",
-        ["<CR>"] = "actions.select",
-        -- ["<C-v>"] = "actions.select_vsplit",
-        ["<C-x>"] = "actions.select_split",
-        ["<C-t>"] = "actions.select_tab",
-        ["<C-p>"] = "actions.preview",
-        ["<C-c>"] = "actions.close",
-        ["<C-l>"] = "actions.refresh",
-        ["-"] = "actions.parent",
-        ["_"] = "actions.open_cwd",
-        ["`"] = "actions.cd",
-        ["~"] = "actions.tcd",
-        ["gs"] = "actions.change_sort",
-        ["gx"] = "actions.open_external",
-        ["g."] = "actions.toggle_hidden",
-        ["g\\"] = "actions.toggle_trash",
-    },
-    view_options = {
-        show_hidden = true,
-    },
-}