Configure rails database pool from env DB_POOL.
Configure rails database pool from env DB_POOL.

Fix sentry errors:

* EVEMONK-BACKEND-56
* EVEMONK-BACKEND-55
* EVEMONK-BACKEND-52
* EVEMONK-BACKEND-51
* EVEMONK-BACKEND-5J
* EVEMONK-BACKEND-53
* EVEMONK-BACKEND-54
* EVEMONK-BACKEND-5H
* EVEMONK-BACKEND-5E
* EVEMONK-BACKEND-5K

biow0lf/evemonk,biow0lf/evemonk,biow0lf/evemonk