FEATURE: add some fuzzy keybindings (#512)

* add `history`, `directories` and `modules` fuzzy keybindings

* add a little README for the bindings

custom-menus/fuzzy/modules.nu

@@ -0,0 +1,24 @@
+{
+    name: fuzzy_module
+    modifier: control
+    keycode: char_u
+    mode: [emacs, vi_normal, vi_insert]
+    event: {
+        send: executehostcommand
+        cmd: '
+            commandline --replace "use "
+            commandline --insert (
+                $env.NU_LIB_DIRS
+                | each {|dir|
+                    ls ($dir | path join "**" "*.nu")
+                    | get name
+                    | str replace $dir ""
+                    | str trim -c "/"
+                }
+                | flatten
+                | input list --fuzzy
+                    $"Please choose a (ansi magenta)module(ansi reset) to (ansi cyan_underline)load(ansi reset):"
+            )
+        '
+    }
+}