Revert "add devise admin user"

This reverts commit 1cc8e1480827d485027c36fbabe05e51285de23f.
Revert "migrate add store ID to Users"

This reverts commit f0ff14f017abecd187cab99018ff2486a6d02dd4.
Revert "set relationships in models"

This reverts commit 255a82d42c8277e6f7cf964a5b3f5cdd213aad33.
Revert "add validation in models"

This reverts commit 65cdd3ec2716853a5b441c6f08fb9babf20a256c.