scroll with zj zk

lua/custom/mappings.lua

@@ -359,6 +359,10 @@ M.movements = {
     -- spell
     ["]s"] = { "]s", "go to next spelling mark" },
     ["[s"] = { "[s", "go to last spelling mark" },
+
+    -- just scroll a line
+    ["zk"] = { "<C-y>", "scroll up a line" },
+    ["zj"] = { "<C-e>", "scroll down a line" },
   },
   v = {
     --big move