Merge pull request #3 from felixsoum/backend-dev

add validation of file type for uploading and corressponding test.
Merge pull request #4 from felixsoum/backend-dev

added model for narrative comment
Fix upload MIME validation
Fix AdminController test removing all narratives
Update NarrativeCount initial value to 1000
Clean up database
Add frontend to CI
Fix Gemfile.lock
Merge pull request #5 from felixsoum/backend

Integrate backend into frontend
Fix narratives backup for test
Fix narratives directory not existing when testing
Merge pull request #6 from felixsoum/backend

Master of merges