Release of version 0.81

Version 0.81 introduces conic sections (ellipse, hyperbola, parabola) as new elements and new chart elements like radar charts. There is also a new shortened syntax for geometric constructions (see http://jsxgraph.uni-bayreuth.de/wiki/index.php/Construct_with_math_syntax).

Beside the usual bug fixes, this release contains improved ticks, arcs and sectors, and animations need much less computing resources, now.

Reading of zip files has been enabled for all browsers, even the IE.

The quality of the Geogebra import has been improved and the import of Cinderella files has been started.

As a further feature JSXGraph contains a color blindness simulation.