Add build option to store profile in HOME directory

On Windows and Linux, we currently include the profile inside the Tor Browser bundle directory. However, this does not work if we want to install Tor Browser in a read-only directory (for instance somewhere in /usr).

We added the --enable-tor-browser-data-outside-app-dir option (which we currently use on macOS), to be able to store the profile in a TorBrowser-Data directory outside the bundle directory, to avoid codesigning issues on macOS. However, I think it is not currently possible to select where the TorBrowser-Data directory is located.

On the tor-packagers mailing list, Thomas Klausner suggested a patch to be able to store the profile in the HOME directory: https://lists.torproject.org/pipermail/tor-packagers/2019-March/000060.html

However, I am not sure if the patch is enough, or if more things are needed to handle updates correctly.