added rakefile and test_story_branch to the gem to start implementing the tests
WIP - added spec structure and spec description for gem tests, added test files to be loadded during tests
WIP - added rspec dependency to gemspec
WIP - raise PIVOTAL_API_KEY exception if api key not found in env. added method to check if object is set with api_key and project_id
removed unecessary files from the struct
searches for existing file or environment set variable. Existing file overrides the env var
clear test files for tests specifications
Finishes #4 test definition
updated code to require gem instead of relative paths