Add editor config & C# conventions

This retires R# settings files.

Author: atifaziz

.editorconfig

@@ -0,0 +1,56 @@
+# http://editorconfig.org/
+
+root = true
+
+[*]
+indent_style = space
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.{csproj,vbproj,vcxproj,vcxproj.filters,proj,projitems,shproj}]
+indent_size = 2
+
+[*.{sln}]
+indent_style = tab
+
+[*.{json,yml}]
+indent_size = 2
+
+[*.{cs,tt,sql}]
+charset = utf-8
+indent_style = space
+indent_size = 4
+max_line_length = 100
+
+[*.cs]
+# Prefer "var" everywhere
+csharp_style_var_for_built_in_types = true:suggestion
+csharp_style_var_when_type_is_apparent = true:suggestion
+csharp_style_var_elsewhere = true:suggestion
+
+# Prefer method-like constructs to have a block body
+csharp_style_expression_bodied_methods = false:none
+csharp_style_expression_bodied_constructors = false:none
+csharp_style_expression_bodied_operators = false:none
+
+# Prefer property-like constructs to have an expression-body
+csharp_style_expression_bodied_properties = true:none
+csharp_style_expression_bodied_indexers = true:none
+csharp_style_expression_bodied_accessors = true:none
+
+# Suggest more modern language features when available
+csharp_style_pattern_matching_over_is_with_cast_check = true:suggestion
+csharp_style_pattern_matching_over_as_with_null_check = true:suggestion
+csharp_style_inlined_variable_declaration = true:suggestion
+csharp_style_throw_expression = true:suggestion
+csharp_style_conditional_delegate_call = true:suggestion
+csharp_prefer_simple_default_expression = true:suggestion
+
+# Spacing
+csharp_space_after_cast = true
+csharp_space_after_keywords_in_control_flow_statements = true
+csharp_space_between_method_declaration_parameter_list_parentheses = false
+
+# Wrapping
+csharp_preserve_single_line_statements = true
+csharp_preserve_single_line_blocks = true