Tests fstab entries before modifying fstab

Checks for the existence of the two needed lines before appending them.
Also happens to use tabs instead of spaces.
Skips a package if one is already installed

The -F switch will skip a package without throwing an error
Additional comments
The file would go in /usr/local/etc/rc.d/unifi
Comments out the rc.conf.local modification, since pfsense won't use it