Warning messages when using "sequelize db:migrate"

[leedongwei]

Steps to reproduce

1. Setup migration config as per documentation
2. Create a dummy migration
3. Run the migration with sequelize db:migrate

Expected behavior

No warning messages when running migration

Actual behavior

Cause

This happens because sequelize migration tool assumes that the migration folder contains only migration scripts. The config and models folders are not valid JS files and caused the warning to be issued.

Fix

Warnings can be avoided by moving all migration scripts into a sub-folder (suggested by @DesignByOnyx on the Slack channel, confirmed when I tested it on my project)