Refined button and background design

- Switched @drawable/x_on_fire_app_icon_gray to
@drawable/x_on_fire_app_icon_gray_bitmap
- Changed log_list_background_gray to new design (same name)
- Changed log_task_button_gray to new design (same name)
- Changed spirituality_icon_gray to new design (same name)
- Changed wellbeing_icon_ray to new design (same name)
- Changed work_icon_gray to new design (same name)
- Switched x_on_fire_app_icon_gray to x_on_fire_app_icon_gray_bitmap