Updated the specified version for the ruby-progressbar to 1.4.1 (the latest 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
Merge pull request #470 from ifi/master

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