Adds support to Travis
capybara 2.1.0 requires Ruby version >= 1.9.3.
Open files relative to the page_examples path.

Fixes #2
Make it ready to be released as a gem

Made it follow the same convention as if it were created with `bundle gem swamp`
Merge pull request #5 from juniorz/gem

Turn the project into a gem
Small changes on .gemspec
Merge pull request #4 from juniorz/issue_2

Open files relative to the page_examples path.
gherkin more declarative than imperative