renamed config.yaml to csv.yaml
added simple migration file for transactions
added sqlite files to gitignore
removed db from root dir
renamed transaction to account_transactions (transaction itself is reserved keyword in activerecord)
renamed transaction to account transaction in specs
added tag class; adjusted tagger
added environment class (establishing connection)
renamed transaction to account transaction in importer class
added tags to migration
added db/migrate dir to gemspec
added nulldb config in spec_helper
added activerecord-nulldb-adapter to development_dependency in gemspec
added Gemfile
Merge branch 'feat/db_storage' into develop