refactor include page/box integration
refactors the way we include common behavior for pages, boxes and resources
Merge branch 'feature/model-include' into develop

* feature/model-include:
  refactors the way we include common behavior for pages, boxes and resources
  refactor include page/box integration
names content page example consistently
uses generated attributes instead of overriding the getters
adds preset_value option to the attribute generator
fixes attribute generator tests
Merge branch 'feature/preset-attribute-values' into develop

* feature/preset-attribute-values:
  fixes attribute generator tests
  adds preset_value option to the attribute generator
Bugfix: newrelic generator now differentiates between deploy key and api key

+ fixes #46
adds preset_attributes and mandatory_attributes option to the model generator
updates CHANGELOG
refactors airbrake into error_tracking generator
checks that the deploy key is used in after_restart.rb
Merge branch 'develop' into feature/video

* develop:
  checks that the deploy key is used in after_restart.rb
  refactors airbrake into error_tracking generator
  updates CHANGELOG
  adds preset_attributes and mandatory_attributes option to the model generator
  Bugfix: newrelic generator now differentiates between deploy key and api key
  fixes attribute generator tests
  adds preset_value option to the attribute generator
  uses generated attributes instead of overriding the getters
  names content page example consistently
  refactors the way we include common behavior for pages, boxes and resources
  refactor include page/box integration

Conflicts:
	CHANGELOG.md