Provide more control over inter-content padding

[0ion9]

It would be nice to have a simple escape code, let's say %+number%, that just advances the x offset by a number of pixels. This would allow finer control, especially of spacing between image elements.

Fine control is currently possible, but only through grossly inefficient and inflexible means -- embedding PNGs containing Nxheight pixels of blank space.

EDIT: rather than a straight number of pixels, it might be more appropriate to express this as a percentage of settings.height. So, if your settings.height = 32, then
%+25% would advance 8 px; but if your settings.height=16, then %+25% would advance 4 px.