~/.irbrc: Reenable completion (why did I disable it? for pry?)

.irbrc

require 'irb/completion'
# Some improvements to irb (coloring + ???)
require 'wirb'
Wirb.start
#require 'wirb'
#Wirb.start
# A history of commands separated by lines.
#  @param hist_file the path to the history file (like ~/.bash_history)