Dark Theme For Graph Control (#1106)

* Added dark them to graph control, started dark theme for the controls on the graph

* Dark theme for graphing mode updated to use event model, diagnostics added, cleaned up code that wasn't needed

* Updated prepare-release-internalonly.yaml internal package version

* Updated Theme Settings properties, removed version change, other small changes from PR feedback>

* Updated the localSettings check and updated the GraphTheme event to send bool instead of string

* Updated the equation line color to change with the graph theme

* Rebased onto master and issues created during the rebase

* Updates per code review feedback

* Update settings properties to just have IsMatchAppTheme property and updated the high contrast settings for the graph control

* Match version to current in master

* Updated per PR feedback

* Fix resetting the m_lastLineColorIndex to only happen when reassignColors is true

* Changed second if to else if in the OnPropertyChanged method

* fixed control button and equation line colors

src/GraphingInterfaces/IGraphingOptions.h

@@ -80,6 +80,10 @@ namespace Graphing
         virtual void SetBoxColor(const Graphing::Color& value) = 0;
         virtual void ResetBoxColor() = 0;
 
+        virtual Graphing::Color GetGridColor() const = 0;
+        virtual void SetGridColor(const Graphing::Color& value) = 0;
+        virtual void ResetGridColor() = 0;
+
         virtual Graphing::Color GetFontColor() const = 0;
         virtual void SetFontColor(const Graphing::Color& value) = 0;
         virtual void ResetFontColor() = 0;