Add overlay option to disable grid drawing.
Reuse drawing code from other editors (timeline editor)
Add argument `display_minor_lines` to function `UI_view2d_draw_lines_x__discrete_frames_or_seconds`
This way minor line drawing can be disabled and so it doesn't cause too much visual noise. Also spacing seems to be too fine so it uses 3x what is defined in preferences.
{F10224091,34474, size=full}