To remove a default keybinding for a particular edit mode, set the `event: null`:
e.g. to disable screen clearing with Ctrl-L
```
let $config = {keybindings: [{
modifier: control
keycode: char_l
mode: [emacs, vi_normal, vi_insert]
event: null
} ]}
```
* updated to reedline generic menus
* help menu with examples
* generic menus in the engine
* description menu template
* list of menus in config
* default value for menu
* menu from block
* generic menus examples
* change to reedline git path
* cargo fmt
* menu name typo
* remove commas from default file
* added error message
* nu-completer with suggestions
* help menu with scrolling
* updates description rows based on space
* configuration for help menu
* update nu-ansi-term
* corrected test for update cells
* changed keybinding
* Refactor usage of is_perf_true to be a parameter passed around
* Move repl loop and command/script execution to nu_cli
* Move config setup out of nu_cli
* Update config_files.rs
* Update main.rs
Co-authored-by: JT <547158+jntrnr@users.noreply.github.com>
