ADD: contribution guide

CHANGELOG.md

@@ -4,6 +4,8 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 and [human-readable changelog](https://keepachangelog.com/en/1.0.0/).
 
 ## Unreleased
+### Added:
+* Contributing guide
 
 ## [0.2.6] 2020-06-05
 ### Changed

CONTRIBUTING.md

@@ -0,0 +1,53 @@
+# Contribution Guidelines
+
+👍🎉 First off, thanks for taking the time to contribute! 🎉👍
+
+## Code of Conduct
+
+Examples of behavior that contributes to creating a positive environment include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a professional setting
+
+## How to Contribute
+
+### Reporting Bugs
+To report bugs, please open an issue containing:
+
+* Clear description of the problem
+* Messages, log entries etc.
+* Example configuration to reproduce the issue
+
+### Suggesting Enhancements
+To suggest an enhancement, open an issue containing:
+
+* Clear description of the feature you are suggesting
+
+### Contribute Code
+We welcome any contribution of code to this repository, from bugfixes to new
+features. In order to simplify code review and speed up the process of adding
+new features, please follow the steps below for every single fix / enhancement.
+Adding multiple features and fixes to one pull request will lead to more
+complicated code review and you risk your changes being declined because of
+things that have nothing to do with them.
+
+Follow these steps to contribute code:
+
+1. Open an issue describing what you want to change (follow one of the previous
+    chapters).
+2. Create a fork and implement your changes
+3. Open a pull request to `develop`
+
+Before submitting the Pull request, make sure to add a description of your
+changes to the changelog.