Update Rails

Signed-off-by: Kyrylo Silin <kyrylosilin@gmail.com>
Wait until DOM is fully loaded

Signed-off-by: Kyrylo Silin <kyrylosilin@gmail.com>
Fix failing tests for Artist and Alias models

Use 'database_cleaner' gem.

Signed-off-by: Kyrylo Silin <kyrylosilin@gmail.com>
Clean DB before execution

Signed-off-by: Kyrylo Silin <kyrylosilin@gmail.com>
Add DatabaseCleaner to minitest_helper.rb

Signed-off-by: Kyrylo Silin <kyrylosilin@gmail.com>
Whoops, I forgot to commit this