added e-ink theme

lua/custom/plugins/e-ink.lua

@@ -0,0 +1,16 @@
+return {
+   "alexxGmZ/e-ink.nvim",
+   priority = 1000,
+   config = function ()
+      require("e-ink").setup()
+      vim.cmd.colorscheme "e-ink"
+
+      -- choose light mode or dark mode
+      -- vim.opt.background = "dark"
+      vim.opt.background = "light"
+      --
+      -- or do
+      -- :set background=dark
+      -- :set background=light
+   end
+}