SBA source has been switched to https.

If you hit the http URL you get redirected to https, which is fine
expect that the imported doesn't like this and throws an error.
Remove USTDA-specific mappings.

TradeEvent::Mappings already has them.
Merge pull request #57 from GovWizely/calum/remove-ustda-mappings-additions

Remove USTDA-specific mappings.
Added api v2 support
Merge pull request #53 from GovWizely/yury/api_v2_migr

Added api v2 support
First commit, import locally.
Started mappings and queries.
Updated mappings, nested queries.
Updated indexing, mapping, and queries.
Added geo_regions and topics fields and queries.
Refactored import methods.
Refactored query methods, import spec.
Added specs.
Uncommented import statement.
Code climate revisions.
Corrected rubocop autoformat fail.
JSON structure revisions.
Updated queries, more revisions.
Import from data folder.
Search_by terms, formatting.