Allow execution of sudo command on hosts

[ns-echen]

$ lsi host-filter -u sshUser -i myKey.pem -c "cd /usr/local/bin; sudo ln -s /usr/bin/python mylink"
[host-filter1 (xx.x.xxx.xxx)]: sudo: sorry, you must have a tty to run sudo
[host-filter2 (xx.x.xxx.xxx)]: sudo: sorry, you must have a tty to run sudo
[host-filter3 (xx.x.xxx.xxx)]: sudo: sorry, you must have a tty to run sudo
[host-filter4 (xx.x.xxx.xxx)]: sudo: sorry, you must have a tty to run sudo

[sfoulkes]

Didn't mean to close this and my comment was incomplete. This is caused by sudo on some OSes being configured to require a tty to run. We could modify lsi to run ssh with a pseudo-tty (-t) but this can cause other problems. Considering that newer versions of redhat/centos removed this requirement (https://bugzilla.redhat.com/show_bug.cgi?id=1020147) we usually just updated the sudo configuration to remove the tty requirement.