Add Base16 Black Metal color scheme

Changes to be committed:
      modified:   lua/colorschemes.lua
      modified:   lua/plugins.lua

Changes not staged for commit:
      modified:   lua/completions.lua

lua/colorschemes.lua

@@ -1,4 +1,31 @@
-local colorscheme = "nord"
+local colorscheme = "base16-black-metal" -- Set colorscheme
+
+if colorscheme == "base16-black-metal" then
+	local ok, base16 = pcall(require, "base16-colorscheme")
+	if not ok then
+		return
+	end
+	base16.setup({
+		--base00 = "#000000",
+		base00 = "#171717",
+		base01 = "#121212",
+		base02 = "#222222",
+		--base03 = "#333333",
+		base03 = "#494949",
+		base04 = "#999999",
+		base05 = "#c1c1c1",
+		base06 = "#999999",
+		base07 = "#c1c1c1",
+		base08 = "#5f8787",
+		base09 = "#aaaaaa",
+		base0A = "#a06666",
+		base0B = "#dd9999",
+		base0C = "#aaaaaa",
+		base0D = "#888888",
+		base0E = "#999999",
+		base0F = "#444444",
+	})
+end
 
 if colorscheme == "onedark" then
 	-- Onedark Default Configuration
@@ -135,6 +162,6 @@ if colorscheme == "nord" then
 	if not ok then
 		return
 	end
-	
+
 	vim.cmd([[colorscheme nord]])
 end

lua/plugins.lua

@@ -4,6 +4,9 @@ if not ok then
 end
 
 packer.startup(function(use)
+	-- Base16 colorscheme
+	use("RRethy/nvim-base16")
+
 	-- Nord colorscheme
 	use("shaunsingh/nord.nvim")