Added support for `--portable-mode` and `--server-datafolder` for the CLI, ServerUtil, and Agent.
Fixed a few places where file reads were not cached properly.
Moved some responsibilities of UpdaterManager into DataFolderManager.
This now supports storing `machineid.txt` and `installation.txt` inside the path pointed to by `--server-datafolder` or alternatively with `--portable-mode`.
It is possible that some fringe backwards compatibility is lost with this update.
Fixed an issue with AutoUpdater crashing on check/download.
This fixes#5902