Remove redundant clear of EULA_ACCEPTED variable.
Convey --fah-* options to updated fahinstall, if necessary.
Add another possibility of skipping Langouste setup (.nolangouste file in client directory).
Retry apt-get commands in case of failure.

apt-get may fail due to not being able to acquire apt lock
(most commonly caused by parallel aptd startup).

Try apt-get commands up to 5 times (every 5 seconds) using bash wrapper
function.