[Menus] Disable Edit menu items when not available

[warpdesign]

Some (native) menus make no sense in some situations.

For example:

File menu

• new tab disabled when

  • downloads active
  • a dialog is opened

• close tab disabled when

  • downloads active
  • a dialog is opened
  • the active view has only one tab

• new folder disabled when:

  • downloads are active
  • folder is readonly
  • a dialog is opened
  • cache.status !== 'ok'

• rename disabled when:

  • downloads are active
  • folder is readonly
  • a dialog is opened
  • no file ore multiple files are selected ?
  • cache.status !== 'ok'

• delete disabled when:

  • downloads are active
  • folder is readonly
  • a dialog is opened
  • no file ore multiple files are selected ?

• open terminal disabled when:

  • downloads are active
  • a terminal is opened
  • cache.options.indirect is true
  • a dialog is opened