Logging updates

Changed the logfile location so that it is stored inside of the gem.
Wiring fix

Added missing 'require' statements and moved them to better spots.
Step enhancements

Added some more tests around step argument scanning and added the
ability to scan based on regular expressions.
Class renaming

Simplified class names.
File renaming

Renamed files to match the new class names.
Documentation update

Added more documentation to some of the classes and modules.
Logging updates

Added specs around the logging module and updated implementation
accordingly.
Spec fix

Fixed an erroneous spec and updated implementation accordingly.
Directory updates

Added more specs around Directory objects and updated implementation
accordingly.
Parsing updates

Added specs around the parsing module and updated implementation
accordingly.
World updates

Added specs around the World module and updated implementation
accordingly.
FeatureFile updates

Added more specs around FeatureFile objects and updated implementation
accordingly.
Spec update

Added an additional spec to better clarify the expected behavior of
'containing' elements and did some minor spec cleanup.
Logging updates

Added to the logging module specs and updated the implementation
accordingly.
New Rake task

Added a task that runs all of the existing tests and made it the
default task.
Tagging updates

Moved tag related code to a shared module in order to have a simple
and consistent way of handling tags.
FeatureElement updates

Added specs around the FeatureElement class for better test
coverage.
Feature updates

Added more specs around the Feature class for better test coverage.
TestElement updates

Added more specs around the TestElement class for better test
coverage.
Background updates

Added more specs around the Background class for better test
coverage.