Migration for Badges and BadgeSets

Rename migration, add constraints, migrate to postgres and config travis

Remove gem sqlite and update rails to 3.2.13

Refactor plain sql in migration to add_foreign_key

Migration refactoring

Migration for Badges and BadgeSets

Rename migration, add constraints, migrate to postgres and config travis

Remove gem sqlite and update rails to 3.2.13

Refactor plain sql in migration to add_foreign_key

Migration refactoring
Merge pull request #16 from artofhuman/feature/models

Migration for Badges and BadgeSets