Join game

See merge request !18

# Conflicts:
#   src/game/coordinate.entity.ts
#   src/game/faction.entity.ts
#   src/game/game.controller.ts
#   src/game/game.dto.ts
#   src/game/game.entity.ts
#   src/game/game.module.ts
#   src/game/game.service.ts
#   src/user/user.entity.ts
#   src/user/user.module.ts

hups

See merge request !16

Type orm

See merge request !14

# Conflicts:
#   src/app.module.ts
#   src/game/game.controller.ts
#   src/game/game.dto.ts
#   src/game/game.entity.ts
#   src/game/game.module.ts
#   src/game/game.service.ts
#   src/user/user.controller.ts
#   src/user/user.entity.ts