Vim config

This change makes a port that creates a default system vimrc.

This is very useful for new users as otherwise vim will default to "compat" mode and act like vi(1).

this compat mode is very bad and has problems with arrows keys on OS X, as well as backspace does not work properly most of the time.

This minor port is made optional for the vim and vim-lite ports to make the FreeBSD UX for vim a lot better.

The code is in phabricator AND on github.

Phabricator: https://reviews.freebsd.org/D1166