Add more complex tools for manipulating the flighttrack

[Joern Ungermann]

The GLORIA limb sounder is capable of evaluating tomographic measurements, which requires dedicated flight patterns, which are typically of polygonal, in effect hexagonal, shape.

Adding such shapes should be supported in table view using a dedicated docked widget.

Modifying the polygonal path later on is also required, but a simple removal of a polygon would work almost as well, if the control remembers the last parameters for simple, slightly changed, re-adding.

[Reimar Bauer]

Reimplemented Hexagon Tools from Stefan using a docking widget for TableView.

Resolve issue #18.

→ <<cset 8c00d3c4a038>>