#275 Added delta values to AxisChangedEventArgs
Fixed build (updated comments)
Better handling of deltas when View min/max is unknown
Updated docs to fix build
Changes after code review:
* Removed GetMinimum() and GetMaximum() methods (replaced by ActualMinimum and ActualMaximum)
* Changed the delta calculation (ActualMinimum - oldActualMinimum)
* Added missing event in Axis.Zoom(double)
Added delta calculations to Axis.Reset
Merge pull request #276 from GeertvanHorrik/pr/deltaeventargs

Added delta values to AxisChangedEventArgs