* Rectangular zoom (you draw a rectangle to set the min and max points)
* Zoom-in mode, the point you selected will be centered.
* Zoom-out mode, the point you selected will be centered.
And:
* Automatic scaling.
* Change  "p/4" to "pi/4" in the scaling dialog

I don't know how to design the UI for the zoom-modes yet. If someone wants to try it, use the keys A,S,D and F (click on the graph widget first) to switch modes.

CCMAIL:kdmoeller@foni.net
CCMAIL:bmlmessmer@web.de

svn path=/trunk/kdeedu/kmplot/; revision=318266