…takes two variables instead of just one.
…s and on failure callback methods.
Sometimes you know what parser class you want to use, so I added `parse_with` for that purpose and then refactored to use it internally. This creates a single point where we're invoking a parser, which sets me up for making other changes. Also added documentation and improved the README entry about passing in your own parsers.
…o filiptepper-travis * 'travis' of https://github.com/filiptepper/feedzirra: remove Ruby 1.9 support from TODO mention required Ruby version in README drop support for Ruby 1.8 trigger travis build disable development tools for Travis build