[freebsd91p7][vim] 1. Re-enable YCM on this machine. 2. Use vi as default git editor.

To disable YCM one-time, run:
$ VIM_DISABLE_YCM=1 vim
[freebsd91p7][vim] 1. Let default VI/VIM read original .vimrc.tiny.

1. Rename .vimrc.tiny to .vimrc.
2. Rename original .vimrc (with all plugins) to .vimrc.rich.
3. Alias vi  => launch vim with .vimrc.
4. Alias vim => launch vim with .vimrc.rich.