Dockerfile: pin gem and bundler versions installed for more repeatable builds
Dockerfile: pin gem and bundler versions installed for more repeatable builds

stevecrozz/errbit,diowa/errbit,cognoa/errbit,bonanza-market/errbit,disvelop/errbit,errbit/errbit,jordoh/errbit,micred/errbit,disvelop/errbit,jordoh/errbit,openSUSE/errbit,cognoa/errbit,stevecrozz/errbit,mikk150/errbit,openSUSE/errbit,bonanza-market/errbit,mak-it/errbit,micred/errbit,bonanza-market/errbit,openSUSE/errbit,mak-it/errbit,cognoa/errbit,jordoh/errbit,errbit/errbit,mak-it/errbit,mikk150/errbit,stevecrozz/errbit,micred/errbit,disvelop/errbit,diowa/errbit,mikk150/errbit,errbit/errbit,diowa/errbit