Add support for creation of users and pages.
Add basic support for creating and updating artworks
Spec new create_artwork and update_artwork methods.
Bump rubocop and fix offenses
Update CHANGELOG and document recently added methods
Merge pull request #3 from joeyAghion/sigma

Add support for creating users and pages
Add helpers for creating a partner
Add helpers for getting an inquiry by id
Merge pull request #4 from ilyakava/partner

@dblock => Add helpers for creating a partner
Add helper for getting all artwork inquiry requests
Merge pull request #5 from ilyakava/inquiry

@dblock => Add helper for getting all artwork inquiry requests
Add helpers for features, ordered sets, and sales
Add helpers for orders and artwork inventory
Add order helper
Purge redundant methods that Hashie provides
Merge pull request #6 from ilyakava/sale

@dblock => Moar Sigma helpers
Ruby 1.9.3 const_get fix
Fix comment typo
Merge pull request #7 from ilyakava/small-fixes

@dblock => 1.9.3 build fix, and fixed comment
Treat inventory as a property of an artwork, not as a resource of its own