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New coloring modes - cumulative distance and angle

Smooth palette creation bugfixes

More customizable interpolation, text-to-image support, miscellaneous…

… fixes

Fixes to spline interpolation, text-to-image writing and histogram co…

…loring

Rank order, coloring improved, brot fractal count filtering added, ne…

…w image interpolation modes

Symbolic mathematics improved, functions no longer need to be space-d…

…elimited

New DoughNut Animation, threading improvements

Exceptions Improved

Minor bugfix in BaseConverter