Add `C-j` and `C-k` to keybinds for picker (#876)

* Add `C-j` and `C-k` for moving down/up in pickers

* Add new binds to keymap doc

book/src/keymap.md

@@ -244,8 +244,8 @@ Keys to use within picker. Remapping currently not supported.
 
 | Key                          | Description       |
 | -----                        | -------------     |
-| `Up`, `Ctrl-p`     | Previous entry    |
+| `Up`, `Ctrl-k`, `Ctrl-p`     | Previous entry    |
-| `Down`, `Ctrl-n`   | Next entry        |
+| `Down`, `Ctrl-j`, `Ctrl-n`   | Next entry        |
 | `Ctrl-space`                 | Filter options    |
 | `Enter`                      | Open selected     |
 | `Ctrl-h`                     | Open horizontally |

helix-term/src/ui/picker.rs

@@ -336,6 +336,10 @@ impl<T: 'static> Component for Picker<T> {
                 code: KeyCode::BackTab,
                 ..
             }
+            | KeyEvent {
+                code: KeyCode::Char('k'),
+                modifiers: KeyModifiers::CONTROL,
+            }
             | KeyEvent {
                 code: KeyCode::Char('p'),
                 modifiers: KeyModifiers::CONTROL,
@@ -349,6 +353,10 @@ impl<T: 'static> Component for Picker<T> {
             | KeyEvent {
                 code: KeyCode::Tab, ..
             }
+            | KeyEvent {
+                code: KeyCode::Char('j'),
+                modifiers: KeyModifiers::CONTROL,
+            }
             | KeyEvent {
                 code: KeyCode::Char('n'),
                 modifiers: KeyModifiers::CONTROL,