message: Add `:up[date]` as alias for `:w[rite]`
diff: @@ -549,7 +549,7 @@ export const builtinExCommands: ReadonlyArray<[[string, string], ArgParser | und
  [['unm', 'ap'], undefined],
  [['unme', 'nu'], undefined],
  [['uns', 'ilent'], undefined],
  - [['up', 'date'], undefined],
  + [['up', 'date'], WriteCommand.argParser],
  [['v', 'global'], undefined],
  [['ve', 'rsion'], undefined],
  [['verb', 'ose'], undefined],
  