FreeBSD updates

To update base system,

1. freebsd-update fetch
2. freebsd-update install
3. freebsd-update rollback

To update jails,

ezjail-admin update -u

TIP: Use freebsd-version to get the version of base system

To upgrade base system,

1. Update the system (see above)
2. Upgrade to a specific release freebsd-update upgrade -r 11.0-RELEASE
3. freebsd-update install
4. reboot
5. freebsd-update install

To upgrade jails,

ezjail-admin update -U -s 10.3-RELEASE

NOTE: I did stumble while upgrading from 10.3 to 11.0, when the upgrade process prompted me to re-install all the `ports` such that all references to the shared libraries are updated properly. However, I completed the upgrade process and later used the following commands to update/upgrade all the installed software.

1. pkg-static install -f pkg
2. pkg upgrade all