Set number and relative number for vim

If you put set number before set relative number, it'll show your current line
number instead of 0
Add alias for todotxt task management: 'pin'

I like to use (A) for my immediate task, and (B) for next tasks in the same
day.  This alias "pins" my current task
Merge branch 'master' of github.com:lionelyoung/dotfiles