Missing keep_numbers in the type of FormatOptions

[anchengjian]

Bug report or Feature request?

Typescript Type Check Error：

(property) keep_numbers: boolean
Type '{ toplevel: true; safari10: true; compress: { ecma: 2015 | 5; arrows: boolean; drop_console: boolean; }; } | { compress: false; toplevel: true; safari10: true; output: { comments: false; keep_numbers: boolean; quote_keys: true; }; }' is not assignable to type 'MinifyOptions'.
  Type '{ compress: false; toplevel: true; safari10: true; output: { comments: false; keep_numbers: boolean; quote_keys: true; }; }' is not assignable to type 'MinifyOptions'.
    Types of property 'output' are incompatible.
      Type '{ comments: false; keep_numbers: boolean; quote_keys: true; }' is not assignable to type 'FormatOptions'.

        Object literal may only specify known properties, and 'keep_numbers' does not exist in type 'FormatOptions'.ts(2322)

Version (complete output of terser -V or specific git commit)

Complete CLI command or minify() options used

terser input

terser output or error

Expected result
Add the keep_numbers type to FormatOptions

[fabiosantoscode]

Pushed a fix now, will release tomorrow!