Updated the specified version for the ruby-progressbar to 1.4.1 (the lat...

...est version).

ruby-progressbar 1.0.2 has an issue when installing the rdocs that breaks the installation of capifony using ‘gem install capifony’
see issue and fix here:
https://github.com/jfelchner/ruby-progressbar/issues/26

I've tested both a clean install and my deploy scripts using this change and nothing broke. Let me know if I can provide any more information.