Revert "Merge pull request #50 from ryansch/capybara-2.1"

This reverts commit 1d421a61e41bcaa3c7ca943f93e3a45cb6dba85a, reversing
changes made to f7c7a338595d27cae50211e5cac2ec598f397f58.
Require capy v2.0.2 for v1.0.x of this gem. Specs pass.