Watch Face Drawing Code (Untested)

Watch Face Drawing Code (Untested)
* Modify APPSCR macros to allow variable number of apps per
  screen, allowing dynamic changing of these values via a
  Settings interface
* Comment old macro code in lcd_homepage_loop
* Add lcd_draw_clock_face to draw a circular clock face with
  hour ticks using trigonometry
* Add lcd_clock_draw_hand to draw clock hands in an easy way
* Modify lcd_clock_loop to use the new lcd_draw_clock_face
  and lcd_clock_draw_hand functions