DOCS: add Discord widget link to README.md & add a disclaimer about semantic commit messages

CONTRIBUTING.md

@@ -2,6 +2,39 @@
 
 If you already cloned the repository and you know that you need to deep dive in the code, here are some guidelines to set up your environment.
 
+### Commits
+
+When making commits, use semantic commit messages system.
+
+Format: `<type>(<scope>): <subject>`
+
+Where `<scope>` is optional.
+
+```
+feat: add synchronous RabbitMQ wrapper
+^--^  ^------------^
+|     |
+|     +-> Summary in present tense.
+|
++-------> Type: chore, docs, feat, fix, refactor, style, or test.
+```
+
+More Examples:
+
+- `feat`: (New feature for the user, not a new feature for build script)
+- `fix`: (Bug fix for the user, not a fix to a build script)
+- `docs`: (Changes to the documentation)
+- `style`: (Formatting, linting)
+- `refactor`: (Refactoring code, eg. renaming a variable)
+- `test`: (Adding missing tests, refactoring tests)
+- `chore`: (Updating grunt tasks etc.)
+
+References:
+
+- https://www.conventionalcommits.org/
+- https://sparkbox.com/foundry/semantic_commit_messages
+- http://karma-runner.github.io/1.0/dev/git-commit-msg.html
+
 ### Virtual environment with `venv`
 
 You can create a virtual environment in a directory using Python's `venv` module:

README.md

@@ -24,6 +24,9 @@
     <a href="https://github.com/Lancetnik/Propan/blob/main/LICENSE" target="_blank">
         <img alt="GitHub" src="https://img.shields.io/github/license/Lancetnik/Propan?color=%23007ec6">
     </a>
+    <a href="https://discord.gg/ChhMXJpvz7" target="_blank">
+        <img alt="Discord" src="https://img.shields.io/discord/1122560426794831872?logo=discord">
+    </a>
 </p>
 
 # Propan

docs/docs/en/contributing/2_contributing-index.md

@@ -2,6 +2,39 @@
 
 If you already cloned the repository and you know that you need to deep dive in the code, here are some guidelines to set up your environment.
 
+### Commits
+
+When making commits, use semantic commit messages system.
+
+Format: `<type>(<scope>): <subject>`
+
+Where `<scope>` is optional.
+
+```
+feat: add synchronous RabbitMQ wrapper
+^--^  ^------------^
+|     |
+|     +-> Summary in present tense.
+|
++-------> Type: chore, docs, feat, fix, refactor, style, or test.
+```
+
+More Examples:
+
+- `feat`: (New feature for the user, not a new feature for build script)
+- `fix`: (Bug fix for the user, not a fix to a build script)
+- `docs`: (Changes to the documentation)
+- `style`: (Formatting, linting)
+- `refactor`: (Refactoring code, eg. renaming a variable)
+- `test`: (Adding missing tests, refactoring tests)
+- `chore`: (Updating grunt tasks etc.)
+
+References:
+
+- https://www.conventionalcommits.org/
+- https://sparkbox.com/foundry/semantic_commit_messages
+- http://karma-runner.github.io/1.0/dev/git-commit-msg.html
+
 ### Virtual environment with `venv`
 
 You can create a virtual environment in a directory using Python's `venv` module:

docs/docs/ru/contributing/2_contributing-index.md

@@ -2,6 +2,39 @@
 
 Если вы уже склонировали репозиторий и уверены, что хотите погрузить в код, вам пригодятся эти гайдлайны для настройки окружения.
 
+### Commits
+
+Когда вы делаете коммиты, пожалуйста, используйте соглашение о семантическом именовании.
+
+Формат: `<type>(<scope>): <subject>`
+
+Где `<scope>` необязателен.
+
+```
+feat: add synchronous RabbitMQ wrapper
+^--^  ^------------^
+|     |
+|     +-> Краткое именование
+|
++-------> Типы: chore, docs, feat, fix, refactor, style, or test.
+```
+
+Больше примеров:
+
+- `feat`: (Новый функционал для пользователей)
+- `fix`: (Багфикс в рамках функционала)
+- `docs`: (Изменения в документации)
+- `style`: (Formatting, linting)
+- `refactor`: (Рефакторинг кода, например изменение названий переменных)
+- `test`: (Добавление или рефакторинг тестов)
+- `chore`: ("обслуживающие" коммиты - повышение версии, апдейт зависимостей и т.д.)
+
+Материалы по теме:
+
+- https://www.conventionalcommits.org/
+- https://sparkbox.com/foundry/semantic_commit_messages
+- http://karma-runner.github.io/1.0/dev/git-commit-msg.html
+
 ### Создайте окружение `venv`
 
 Как и любой *python* проект, **Propan** лучше разрабатывать в отдельном окружении.