Add editorconfig file

.editorconfig

@@ -0,0 +1,27 @@
+# To learn more about .editorconfig see https://aka.ms/editorconfigdocs
+###############################
+# Core EditorConfig Options   #
+###############################
+# All files
+[*]
+indent_style = space
+
+# XML project files
+[*.{csproj,vcxproj,vcxproj.filters,proj,projitems,shproj}]
+indent_size = 2
+
+# XML config files
+[*.{props,targets,ruleset,config,nuspec,resx,vsixmanifest,vsct}]
+indent_size = 2
+
+# Code files
+[*.{cs,csx}]
+indent_size = 4
+insert_final_newline = true
+charset = utf-8-bom
+###############################
+# .NET Coding Conventions     #
+###############################
+[*.{cs}]
+# Organize usings
+dotnet_sort_system_directives_first = true