Experimental: freshly seeded particles start their first location search in the cell they were placed in, rather than searching from scratch. This applies to Volume, to Surface and SurfaceEdges on ranks that hold the inlet, and to PointSource, whose particles go directly to the rank owning the point. Particle locations are unchanged. The initial settlement of 262,144 Volume particles on a 64^3 box dropped from 192 s to 18 s (debug build).