Use user home directory as initial dirOut (instead of /root)

[bitsgalore]

But see: #19, pkexec makes this quite difficult.

[bitsgalore]

What might work:

• store values of SUDO_UID, SUDO_GID and SUDO_USER in global (not user-specific, since user homedir cannot be established from env variables!!) config file which is created by config script.
• Then read values in config.py and make them available to all modules

See also:
https://stackoverflow.com/questions/1024114/location-of-ini-config-files-in-linux-unix

But this will create problems if machine has multiple users/accounts.

[bitsgalore]

Now uses SUDO_USER value from config file.