Refresh Visual Studio Code list of files

EDIT: In the meanwhile a reload button has been added to the file explorer widget.

Use the workbench.action.reloadWindow command.
Go to File -> Preferences -> Keyboard Shotcuts and define a shortcut for this command. On my system it’s placed on Ctrl+F5. The entry in keybindings.json looks like this:

{
  "key": "ctrl+f5",
  "command": "workbench.action.reloadWindow",
  "when": "editorTextFocus"
}