So add details by hand!

Well Dave gave you an alternate solution above. Having a plugin that specific does not seem very practical. Either take the time to model the gap between cabinet doors or fake it. Either Dave's way or after the rendering just strike a line in your photo editor of choice. Personally I would just take the extra time to model the details I want to see in the rendering. It makes for a more realistic result. My 2 cents.

Select the edge Activate Move + Ctrl Pick a start point Move the edge in the desired direction Type the distance desired + <enter> [say 6] The copy of the edge is made moved 6 units in that direction Immediately typing another distance changes the moved amount Next immediately type the number of copies you want, followed by x and <enter> So for 10 copies that'd be 10x The moved edge is replicated 10 times in the direction you chose, beyond the first copy, using the same distance each time... To copy a number of edges between the original and the first copy's position use /10 instead... then the space between the original edge and the first copy is subdivided with new duplicates, evenly spaced to fit in...