DRY up consolidated models.

Fixes [#78695166].
Added empty array instead of null return for api v2. Api v1 returns null
Merge pull request #56 from GovWizely/calum/dry-up-consolidated-models

DRY up consolidated models.
Merge pull request #64 from GovWizely/yury/blank_returns

Added empty array instead of null return for api v2. Api v1 returns null
Support for ita office locations endpoint to be queried by countries in v2 and country in v1 API
Merge pull request #65 from GovWizely/yury/trade_articles_countries_support

Support for ita office locations endpoint to be queried by countries in ...
Removed rescue from importer, API V2 support.
Code coverage revisions.
Remove SharepointHelpers module.
Terser SharepointTradeArticleData#import.