Fallback to operation without rclextract fails

[bheorcnh]

Due to a wrong wsgi user configuration, the line
from recoll import rclextract
threw an exception as a result from
mkdir(/usr/share/httpd/.recoll) failed: Permission denied
This is correct behaviour until here.
But as a result
import recoll
was called in the exception handler instead of
from recoll import recoll
This resulted in an error
AttributeError: 'module' object has no attribute 'connect',
later in line
db = recoll.connect(config['confdir'])
where it is difficult to find the reason for.