Move Nix files into a nix directory

Move everything from `config` to the root level.

nvim/after/ftplugin/gitcommit.lua

@@ -0,0 +1,8 @@
+vim.opt_local.colorcolumn = "50,72"
+vim.opt_local.spell = true
+vim.opt_local.textwidth = 72
+
+-- autocmd FileType gitcommit highlight ColorColumn ctermbg=8
+-- filetype indent on
+-- filetype on
+-- filetype plugin on

nvim/after/ftplugin/markdown.lua

@@ -0,0 +1,5 @@
+-- TODO: Interim fix for https://github.com/nvim-treesitter/nvim-treesitter-context/issues/431.
+require("treesitter-context").disable()
+
+vim.opt_local.spell = true
+vim.opt_local.wrap = true

nvim/after/ftplugin/rst.lua

@@ -0,0 +1,13 @@
+local opt = vim.opt_local
+
+opt.spell = true
+opt.wrap = true
+
+local cmp = require "cmp"
+local sources = cmp.get_config().sources
+
+-- TODO: confirm these aren't aleady in the list of sources to avoid duplicate suggestions.
+table.insert(sources, { name = "buffer" })
+table.insert(sources, { name = "path" })
+
+cmp.setup.buffer { sources = sources }

nvim/after/ftplugin/term.vim

@@ -0,0 +1,4 @@
+setlocal norelativenumber
+setlocal nonumber
+
+setlocal scrolloff=0