Added examples conf files for several httpd
Bind unicorn to tcp by defaultto ease configuration with apache and lighttpd
in their current Debian versions.
Ease the override of DAEMON_ARGS in init script and provide a /etc/default/isso
with instructions to run on unix socket
Updated systemd file to bind to tcp by default
typo USR->USER
Merge pull request #5 from JocelynDelalande/doc-httpd-usability

Ease integration with httpd's (incl. TCP gunicorn bind)