[50] Logs

[JaRutkowski]

Give the superuser the possibility to check build logs in the application.

Build logs should be fetched via REST API. Logs can be fetched with output_stream_url (heroku/builds method).

PSB:

com.javafee.elibrary.rest.api.service.heroku.HerokuManagementService
//TODO Implement logs fetching method

Connected with #282 (this option could be placed in 'Settings' under 'Installation' - similarly to:

• Give the admin user the possibility to check the db logs;
• Give the admin user the possibility to check the db version (f.eg. orderexecuted.deployment_id);).