Use simple require for spec helper
Add specs for API v2 version index
Add specs for API v2 version show
Extract methods used for multiple project selection
Implement version index with multiple projects
Test handling of shared versions
Query projects shared versions
Test projects references in shared versions
Aggregate projects for shared versions
Remove show endpoint
Test version ids filter
Implement version ids filter
Test API v2 version index response
Implement API v2 version index response