Added benchmarking script for Lexer.

# Script for benchmarking the lexer.

#

# Takes bunch of filenames as arguments and runs them all through lexer.

#

$:.unshift File.dirname(File.dirname(__FILE__)) + "/lib"

require 'jsduck/lexer'

ARGV.each do |fname|

  JsDuck::Lexer.new(IO.read(fname))

end