Also adds a nxdt::views::EtaProgressInfo struct that's used by EtaProgressDisplay's setProgress() method. It may also be used by child classes of AsyncTask.
Other changes include:
* DownloadTask: remove DownloadTaskProgress struct, update logic to use the new nxdt::views::EtaProgressInfo struct.
* DumpOptionsFrame, GameCardTab: minor formatting fixes.
* OptionsTab: remove OptionsTabUpdateProgress class, update logic to use the new nxdt::views::EtaProgressInfo struct.
