Nuget tweaks for CI testing (C#)

Author: AngusJohnson

CSharp/NuGet/License.txt

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+Boost Software License - Version 1.0 - August 17th, 2003
+
+Permission is hereby granted, free of charge, to any person or organization
+obtaining a copy of the software and accompanying documentation covered by
+this license (the "Software") to use, reproduce, display, distribute,
+execute, and transmit the Software, and to prepare derivative works of the
+Software, and to permit third-parties to whom the Software is furnished to
+do so, all subject to the following:
+
+The copyright notices in the Software and this entire statement, including
+the above license grant, this restriction and the following disclaimer,
+must be included in all copies of the Software, in whole or in part, and
+all derivative works of the Software, unless such copies or derivative
+works are solely in the form of machine-executable object code generated by
+a source language processor.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
+SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
+FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.

CSharp/NuGet/README.md

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+# Clipper2
+### A Polygon Clipping, Offsetting, and Triangulation library (in C++, C# & Delphi)
+[![License](https://img.shields.io/badge/License-Boost_1.0-lightblue.svg)](https://www.boost.org/LICENSE_1_0.txt)
+[![documentation](https://user-images.githubusercontent.com/5280692/187832279-b2a43890-da80-4888-95fe-793f092be372.svg)](http://www.angusj.com/clipper2/Docs/Overview.htm)
+
+**Clipper2** is a major update of my original [**Clipper library**](https://sourceforge.net/projects/polyclipping/) which I'm now calling **Clipper1**. Clipper1 was written 15 years ago and still works very well, but Clipper2 is better.
+
+ 
+### Example
+
+      Paths64 subj = new Paths64();
+      Paths64 clip = new Paths64();
+      subj.Add(Clipper.MakePath(new int[] { 100, 50, 10, 79, 65, 2, 65, 98, 10, 21 }));
+      clip.Add(Clipper.MakePath(new int[] { 98, 63, 4, 68, 77, 8, 52, 100, 19, 12 }));
+      Paths64 solution = Clipper.Intersect(subj, clip, FillRule.NonZero);
+      
+![clipperB](https://user-images.githubusercontent.com/5280692/178123810-1719a1f5-25c3-4a9e-b419-e575ff056272.svg)