Log Message:
Changes  4.6.5:
* NEW monotonic cubic splines using "smooth mcsplines"
* NEW phase-jump removal filter "smooth unwrap"
* NEW allow '+' pseudofile to sample the T axis in 2D parametric plots
* NEW allow '++' pseudofile to sample the U/V axes in 3D parametric plots
* NEW "sixel" terminal driver
* NEW new object attribute clip/noclip
* CHANGE maximum number of using spec columns increased from 7 to 11
* CHANGE code in bitmap.c relicensed to remove restriction to noncommercial use
* FIX allow 'set pm3d' interpolate and top/bottom options to coexist
* FIX revised handling of defined palettes with explicit maxcolors
* FIX continue as normal after an interactive session error from "gnuplot \ 
-"
* FIX empty first field in a tab-separated-values file was incorrectly ignored
* FIX several problems with color assignment to contour lines
* FIX qt terminal incorrectly changed linetype (dot/dash) to match line color
* FIX "pause mouse" worked only for right- or center- click, not left-click
* FIX emf terminal font initialization
* FIX wxt terminal vertical centering of enhanced text
* FIX win terminal filled polygon bugs
* FIX iteration over parametric function plots
* FIX autoscaling of polar mode plots
* FIX increase precision of xticlabel placement from (float) to (double)
* FIX allocation error affecting certain cvs files