Added tests for attributes with type defined.
Also improved timestamp attributes. Now is possible to pass a DateTime
or Date object and it will convert it correctly.
Lock down rest-client version on ruby 1.8.7
Fixed tests on ruby 1.8.7
Removing Hour from output to fix time zone issues on test
Checking for method implementation instead of rescuing NoMethodError as suggested by @geemus
Merge pull request #52 from zertico/improving_attributes

Testing attribute definition