refactoring: use THISDIRECTORY PARENTDIRECTORY
refactoring: Engine::AddFile
refactoring: rename functions
refactoring: extract function Engine::AddFile2
refactoring: Engine::AddFile: remove goto fin
refactoring: extract function Engine::MainFinalize
refactoring: Engine::Main: remove goto fin
refactoring: Engine::Copy: remove goto abort
refactoring: Engine::FlushBuff: remove goto skip
refactoring: Engine::Copy: remove goto skip
refactoring: Engine::Copy: cleanup
version info: update
remove const String emptyString;
Engine::Copy: fix
refactoring: Engine::Copy: remove goto skip
refactoring: Engine::CheckOverwrite3
refactoring: Engine::CheckDstFileExists: remove goto rep
refactoring: bool AcceptForAll
fix code style (var declarations)
refactoring: Engine::CheckOverwrite3