ordinal case insensitive sorting for suggestions

Author: jonsequitur

src/System.CommandLine.Suggest.Tests/DotnetSuggestEndToEndTests.cs

@@ -155,7 +155,7 @@ await Process.ExecuteAsync(
 
             stdOut.ToString()
                 .Should()
-                .Be($"/?{NewLine}/h{NewLine}-?{NewLine}--apple{NewLine}--banana{NewLine}--cherry{NewLine}--durian{NewLine}-h{NewLine}--help{NewLine}--version{NewLine}");
+                .Be($"--apple{NewLine}--banana{NewLine}--cherry{NewLine}--durian{NewLine}--help{NewLine}--version{NewLine}-?{NewLine}-h{NewLine}/?{NewLine}/h{NewLine}");
         }
     }
 }

src/System.CommandLine/Argument.cs

@@ -192,7 +192,7 @@ public override IEnumerable<string> GetSuggestions(string textToMatch = null)
                    .Concat(dynamicSuggestions)
                    .Concat(typeSuggestions)
                    .Distinct()
-                   .OrderBy(c => c)
+                   .OrderBy(c => c, StringComparer.OrdinalIgnoreCase)
                    .Containing(textToMatch);
         }
 

src/System.CommandLine/Symbol.cs

@@ -146,7 +146,7 @@ public virtual IEnumerable<string> GetSuggestions(string textToMatch = null)
             return this.ChildSymbolAliases()
                        .Concat(argumentSuggestions)
                        .Distinct()
-                       .OrderBy(symbol => symbol)
+                       .OrderBy(symbol => symbol, StringComparer.OrdinalIgnoreCase)
                        .Containing(textToMatch);
         }