Export notes to HTML format

* i would like to select
  - "view/export this item"
  - "view/export selected items"
  - "view/export all items"

* a context menu should be provided

* a hotkey/shortcut should be available

* Options for export
  [ ] title only
  [ ] only items entered after [dd.mm.yyyy]

* data should be ordered the same as the result list,
  e.g. desc/asc sorting

* Use the same font for title and text as configured in CN options
  for displaying in html. This is especially meaningful when courier
  font is used.

Thanks for the suggestions! I will take them into account when implementing this feature.