Add global usings (#668)

* Use global usings

* Fix namespace declarations for test projects

src/Spectre.Console/Cli/Internal/Modelling/CommandArgument.cs

@@ -1,8 +1,3 @@
-using System;
-using System.Collections.Generic;
-using System.ComponentModel;
-using System.Reflection;
-
 namespace Spectre.Console.Cli;
 
 internal sealed class CommandArgument : CommandParameter

src/Spectre.Console/Cli/Internal/Modelling/CommandContainerExtensions.cs

@@ -1,5 +1,3 @@
-using System.Linq;
-
 namespace Spectre.Console.Cli;
 
 internal static class CommandContainerExtensions

src/Spectre.Console/Cli/Internal/Modelling/CommandInfo.cs

@@ -1,9 +1,3 @@
-using System;
-using System.Collections.Generic;
-using System.ComponentModel;
-using System.Linq;
-using System.Reflection;
-
 namespace Spectre.Console.Cli;
 
 internal sealed class CommandInfo : ICommandContainer

src/Spectre.Console/Cli/Internal/Modelling/CommandInfoExtensions.cs

@@ -1,5 +1,3 @@
-using System.Linq;
-
 namespace Spectre.Console.Cli;
 
 internal static class CommandInfoExtensions

src/Spectre.Console/Cli/Internal/Modelling/CommandModel.cs

@@ -1,9 +1,3 @@
-using System;
-using System.Collections.Generic;
-using System.Diagnostics;
-using System.IO;
-using System.Reflection;
-
 namespace Spectre.Console.Cli;
 
 internal sealed class CommandModel : ICommandContainer

src/Spectre.Console/Cli/Internal/Modelling/CommandModelBuilder.cs

@@ -1,9 +1,3 @@
-using System;
-using System.Collections.Generic;
-using System.ComponentModel;
-using System.Linq;
-using System.Reflection;
-
 namespace Spectre.Console.Cli;
 
 internal static class CommandModelBuilder

src/Spectre.Console/Cli/Internal/Modelling/CommandModelValidator.cs

@@ -1,7 +1,3 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-
 namespace Spectre.Console.Cli;
 
 internal static class CommandModelValidator

src/Spectre.Console/Cli/Internal/Modelling/CommandOption.cs

@@ -1,8 +1,3 @@
-using System;
-using System.Collections.Generic;
-using System.ComponentModel;
-using System.Reflection;
-
 namespace Spectre.Console.Cli;
 
 internal sealed class CommandOption : CommandParameter

src/Spectre.Console/Cli/Internal/Modelling/CommandParameter.cs

@@ -1,9 +1,3 @@
-using System;
-using System.Collections.Generic;
-using System.ComponentModel;
-using System.Linq;
-using System.Reflection;
-
 namespace Spectre.Console.Cli;
 
 internal abstract class CommandParameter : ICommandParameterInfo

src/Spectre.Console/Cli/Internal/Modelling/CommandParameterComparer.cs

@@ -1,5 +1,3 @@
-using System.Collections.Generic;
-
 namespace Spectre.Console.Cli;
 
 internal static class CommandParameterComparer

src/Spectre.Console/Cli/Internal/Modelling/ICommandContainer.cs

@@ -1,5 +1,3 @@
-using System.Collections.Generic;
-
 namespace Spectre.Console.Cli;
 
 /// <summary>

src/Spectre.Console/Cli/Internal/Modelling/ParameterKind.cs

@@ -1,5 +1,3 @@
-using System.ComponentModel;
-
 namespace Spectre.Console.Cli;
 
 internal enum ParameterKind