Move WixBuildTools into internal

src/.editorconfig renamed

src/internal/CSharp.Build.props renamed

src/internal/Cpp.Build.props renamed

src/internal/Directory.Build.props renamed

src/internal/Directory.Build.targets renamed

src/internal/MessagesToMessages/MessagesToMessages.csproj renamed

src/internal/MessagesToMessages/Program.cs renamed

src/internal/MessagesToMessages/Properties/launchSettings.json renamed

src/internal/MessagesToMessages/SimpleJson.cs renamed

src/internal/README.md renamed

src/internal/TablesAndTuples/ColumnDefinitionEnums.cs renamed

src/internal/TablesAndTuples/Program.cs renamed

src/internal/TablesAndTuples/SimpleJson.cs renamed

src/internal/TablesAndTuples/TablesAndTuples.csproj renamed

src/internal/TablesAndTuples/WixColumnDefinition.cs renamed

src/internal/TablesAndTuples/WixTableDefinition.cs renamed

src/internal/WixBuildTools.MsgGen/AssemblyInfo.cs renamed

src/internal/WixBuildTools.MsgGen/GenerateMessageFiles.cs renamed

src/internal/WixBuildTools.MsgGen/MsgGen.cs renamed

src/internal/WixBuildTools.MsgGen/WixBuildTools.MsgGen.csproj renamed

src/internal/WixBuildTools.MsgGen/Xsd/messages.xsd renamed

src/internal/WixBuildTools.MsgGen/build/WixBuildTools.MsgGen.targets renamed

src/internal/WixBuildTools.MsgGen/buildCrossTargeting/WixBuildTools.MsgGen.targets renamed

src/internal/WixBuildTools.TestSupport.Native/AssemblyInfo.cpp renamed

src/internal/WixBuildTools.TestSupport.Native/NativeAssert.h renamed

src/internal/WixBuildTools.TestSupport.Native/WixBuildTools.TestSupport.Native.nuspec renamed

src/internal/WixBuildTools.TestSupport.Native/WixBuildTools.TestSupport.Native.vcxproj renamed

src/internal/WixBuildTools.TestSupport.Native/WixBuildTools.TestSupport.Native.vcxproj.filters renamed

src/internal/WixBuildTools.TestSupport.Native/build/WixBuildTools.TestSupport.Native.props renamed

src/internal/WixBuildTools.TestSupport.Native/build/WixBuildTools.TestSupport.Native.targets renamed

src/internal/WixBuildTools.TestSupport.Native/packages.config renamed

src/internal/WixBuildTools.TestSupport.Native/precomp.cpp renamed

src/internal/WixBuildTools.TestSupport.Native/precomp.h renamed

src/internal/WixBuildTools.TestSupport/Builder.cs renamed

src/internal/WixBuildTools.TestSupport/DisposableFileSystem.cs renamed

src/internal/WixBuildTools.TestSupport/DotnetRunner.cs renamed

src/internal/WixBuildTools.TestSupport/ExternalExecutable.cs renamed

src/internal/WixBuildTools.TestSupport/ExternalExecutableResult.cs renamed

src/internal/WixBuildTools.TestSupport/FakeBuildEngine.cs renamed

src/internal/WixBuildTools.TestSupport/MsbuildRunner.cs renamed

src/internal/WixBuildTools.TestSupport/MsbuildRunnerResult.cs renamed

src/internal/WixBuildTools.TestSupport/Pushd.cs renamed

src/internal/WixBuildTools.TestSupport/Query.cs renamed

src/internal/WixBuildTools.TestSupport/RobocopyRunner.cs renamed

src/internal/WixBuildTools.TestSupport/SucceededException.cs renamed

src/internal/WixBuildTools.TestSupport/TestData.cs renamed

src/internal/WixBuildTools.TestSupport/TestDataFolderFileSystem.cs renamed

src/internal/WixBuildTools.TestSupport/VswhereRunner.cs renamed

src/internal/WixBuildTools.TestSupport/WixAssert.cs renamed

src/internal/WixBuildTools.TestSupport/WixBuildTools.TestSupport.csproj renamed

src/internal/WixBuildTools.XsdGen/AssemblyInfo.cs renamed

src/internal/WixBuildTools.XsdGen/CodeDomInterfaces.cs renamed

src/internal/WixBuildTools.XsdGen/CodeDomReader.cs renamed

src/internal/WixBuildTools.XsdGen/ElementCollection.cs renamed

src/internal/WixBuildTools.XsdGen/StronglyTypedClasses.cs renamed

src/internal/WixBuildTools.XsdGen/WixBuildTools.XsdGen.csproj renamed

src/internal/WixBuildTools.XsdGen/XsdGen.cs renamed

src/internal/WixBuildTools.XsdGen/build/WixBuildTools.XsdGen.targets renamed

src/internal/WixBuildTools.XsdGen/buildCrossTargeting/WixBuildTools.XsdGen.targets renamed

src/internal/WixBuildTools.sln renamed

src/internal/WixBuildTools.v3.ncrunchsolution renamed

src/internal/appveyor.cmd renamed

src/internal/appveyor.yml renamed

src/internal/nuget.config renamed

src/version.json renamed