minor: align def and end [skip ci]
style: use ruby 1.9 style hashes
File.exists? is deprecated since ruby 1.9 it seems
do not rescue Exception - default is StandardError

calls to exit and kill signals will be caught (except kill -9) with rescue Exception - not what we want
minor: no need to use .to_s in interpolation
use StandardError not Exception

Exception is the superclass of all errors and Interrupts. You don't
want to mess with that.

If you just call
  raise 'error message'
it will create a RuntimeError and that will be caught by
  rescue exc
as that catches StandardError.

You don't want to call raise Exception.new or inherit from Exception
because that would not get caught by rescue like that.

You don't want to rescue Exception => exc - because that would also
rescue from Interrupts like CTRL+c.
Merge pull request #59 from azul/style/basic-rubocop

Style/basic rubocop