Add specs :) Both local (gigs) and remote (github)

Move the content of github.com/rspec-api/gigs into the spec folder.
Now running `rspec` tests the `rspec-api` features both against a
local spec/dummy (a Rails app listing concerts) and against the
remote GitHub API.

Unit/function tests will be coming later, but for now this shows
how rspec-api works!

In order to run the github specs, a local .github file with the
Github token is required
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