Revert "Fix cloud_files gemspec: nokogiri <1.10 for ruby <2.3"
Revert "Fix cloud_files gemspec: nokogiri <1.10 for ruby <2.3"

This reverts commit 1e9feb072d21d8032cf7366f31be697f935d1064.

testfairy/dpl,testfairy/dpl,travis-ci/dpl,testfairy/dpl,travis-ci/dpl,travis-ci/dpl