Edited Feature: Define axis constraints [10095]

Types of constraints
A. Two axes (e.g. X and Y) should be equally scaled (currently PlotType.Cartesian)
B. Two axes should be proportionally scaled
C. Align two axes at specified values (e.g. always keep 0 aligned, but allow different scale)
D. Set proportional scaling and alignment at specified values (e.g. showing celsius and fahrenheit)

It should also be possible to have linked constraints, but no loops.


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Add `Constraint` to Axis class or a list `Constraints` to the PlotModel class

AxisConstraint constructors
```c#
AxisConstraint(Axis otherAxis, double scale)
AxisConstraint(Axis otherAxis, double thisAlignmentValue, double otherAlignmentValue)
AxisConstraint(Axis otherAxis, double scale, double thisAlignmentValue, double otherAlignmentValue)
```
A. `axis1.Constraint = new AxisConstraint(axis2, 1);`
B. `axis1.Constraint = new AxisConstraint(axis2, 2);`
C. `axis1.Constraint = new AxisConstraint(axis2, 0, 0);`
D. `axis1.Constraint = new AxisConstraint(axis2, 9d/5, 0, 32);`

or can you suggest something better?

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Is [issue:10033] related?