Remember dock position
Fix few places where SyntaxWarning used to be thrown from Python

The idiom "from X import *" is valid only in global scope
Fixed min/max contour values.

It's not possible to enter text anymore, also reacting on every text change for immediate feedback.
Fixed crash when failed to open 2DM file for a DAT file.

Also cleaned up a bit initialization and destruction of internal structures.
Fixed the problem with zoomed out triangles + fixed problem with invalid triangles