Revert "camera import: don't compile it by default, it's dangerous."

This reverts commit ea276e40e0e4aa7d77c839aaa629b48e13f12529.
Removes support for deleting images from camera.

This option has proved to be dangerous and should anyway never be used.
It is far safer to keep the pictures on the sd/xd/cf card and letting
time to develop and put the pictures on a safe storage (RAID, external
storage service...). Then when a card is to be reused it can be formatted
on the camera.
Merge branch 'enable-safe-camera-import'

* enable-safe-camera-import:
  Removes support for deleting images from camera.
  Revert "camera import: don't compile it by default, it's dangerous."