Feature: token endpoint

[borisrizov-zf]

Description

This is a copy of the PR by mgora, #179, as he won't be able to continue working on the branch.

Pre-review checks

Please ensure to do as many of the following checks as possible, before asking for committer review:

• [x] DEPENDENCIES are up-to-date. Dash license tool. Committers can open IP issues for restricted libs.
• [x] Copyright and license header are present on all affected files

[sonarcloud[bot]]

Quality Gate passed

The SonarCloud Quality Gate passed, but some issues were introduced.

6 New issues
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[borisrizov-zf]

Closed in favor of #249