Use default values from default bundle configuration instead of hardcoded constants

Problem/Motivation

This task is a follow-up to this comment.
Basically, we should review and replace (where possible) usages of constants with default configuration object, that will be used for default values for new bundles.

Proposed resolution

Get default values for bundle/entities in the following order:
1) Default configuration object;
2) Current default values set in constants if the configuration is empty (it can be removed manually);