Apply the new popup menu icon to the loaded JFace icons/full copy

JFaceResources registers POPUP_IMG_MENU with icons/full/popup_menu.svg as
the primary resource and uses the class-relative dialogs/images copy only as
a non-OSGi fallback, so the earlier swap that only touched dialogs/images was
invisible inside a running Eclipse. Copy the three-dots artwork into
icons/full so PopupDialogs such as Quick Access render the new glyph.

Author: vogella