feat(ft): added objc support (#412)

Add support for Objective-C family of files.

Author: bananartist

lua/Comment/ft.lua

@@ -117,6 +117,8 @@ local L = setmetatable({
     nim = { M.hash, '#[%s]#' },
     nix = { M.hash, M.cxx_b },
     nu = { M.hash },
+    objc = { M.cxx_l, M.cxx_b },
+    objcpp = { M.cxx_l, M.cxx_b },
     ocaml = { M.fsharp_b, M.fsharp_b },
     odin = { M.cxx_l, M.cxx_b },
     plantuml = { "'%s", "/'%s'/" },