add tests with Ruby 2, and deprecate CI testing for 1.8/1.9.2
\#3 add a basic spec for mandrill signature handling
add change log note and attribution for 0.0.5
\#3 refactor webhook authentication support

* NB: a new method for configuring the web hook api keys
tweak some guard options
shouldn't really include the .rspec config in the repo

* peeps can set their own general prefs in ~/.rspec
\#3 moved the authentication recipes to a more prominent place in the README
step to 1.0.0

* make it official
* applying Semantic Versioning principles; see http://semver.org/
fix some readme typos
Slight refactor to consistently use the request passed as a parameter instead of pulling the request off the callback_host in one place.
Refactored Mandrill signature authentication to a separate method meant to be used as a before_filter.
Described refactored signature authentication syntax in README.