v3.0.5

Bugfix: negative rho is fixed. This was caused by dc==0 (radius of the neighbor-finding spheres)
when the median distance-cutoff was zero. This is fixed by discarding zero-distance values before
calculating the quantile values.

Display fix: curves in rho-delta plot (bottom-right plot in the manual view) is suppressed.
These spikes come from delta==0 values whose nearest pair has exactly same feature scores.
These spikes are now hidden from the display.