Track backup and restore progress based on the sizes of the files
as they are being added to the tar backup file. Update the
progress bar based on the sizes of the files.
Change-Id: Idf649efa1db3e91830b4b2add86203a3f30042ff
twrpDU::check_skip_dirs() handles skipped folders now. Everywhere
twrpTar::setexcl() is being used to exclude files eventually calls
createTarFork(), which in turn calls Generate_TarList(), which checks
check_skip_dirs().
Change-Id: Ibbc4eb2eb89863ccb2a15f5a3b5092fb10fcbcc0