Anki add-on: FULLER SCREEN: hide top toolbar in reviewer

This add-on hides the top toolbar during review of cards. It helps save screen space. Press D to return to the main menu. For an add-on that hides the bottom toolbar too (the answer buttons, partially hidden or even completely), see here: https://ankiweb.net/shared/info/1999609504 CREDIT ================================================= Credit: Original code by Steve AW. Edited by Joseph Yasmeh to port to Anki 2.1.