New UX testing subsection

Created new UX testing subsection for Uier, Selenoid, and Zalenium as per @nodiscc 's suggestion.

README.md

@@ -78,6 +78,7 @@ See [Contributing](.github/CONTRIBUTING.md).
     - [Bug Trackers](#bug-trackers)
     - [IDE/Tools](#idetools)
     - [Continuous Integration](#continuous-integration)
+    - [UX testing](#ux-testing)
     - [FaaS/Serverless](#faasserverless)
     - [API Management](#api-management)
     - [Documentation Generators](#documentation-generators)
@@ -1223,16 +1224,19 @@ See **[Ticketing](#ticketing)**
 - [Regexr](http://regexr.com/) - RegExr is a HTML/JS based tool for creating, testing, and learning about Regular Expressions. ([Source Code](https://github.com/gskinner/regexr)) `MIT` `Nodejs`
 - [RequestBin](https://requestb.in/) - Inspect HTTP requests. Debug webhooks. ([Source Code](https://github.com/Runscope/requestbin)) `MIT` `python`
 - [RStudio Server](https://www.rstudio.com/products/rstudio/#Server) - Web browser based IDE for R. ([Source Code](https://github.com/rstudio/rstudio)) `AGPL-3.0` `Java/C++`
-- [Selenoid](http://aerokube.com/selenoid/latest/) - Lightweight Selenium hub implementation launching browsers within Docker containers. ([Source Code](https://github.com/aerokube/selenoid)) `Apache-2.0` `Go`
 - [sourcegraph](https://sourcegraph.com) - Sourcegraph is a fast, open-source, fully-featured code search and navigation engine written in Go. ([Source Code](https://github.com/sourcegraph/sourcegraph)) `Apache-2.0` `Go`
-- [Uier](https://github.com/sjoerdvanderhoorn/Uier) - Codeless or low-code User Experience test editing and management using Selenium to perform testing or UI automation. Uier tends to be a free self hostable alternative to Applitools, Endtest, Ghost Inspector, Usetrace, Screenster and many others. `Apache-2.0` `Nodejs`
 - [Wide](https://github.com/b3log/wide) - Web-based IDE for Teams using Go programming language/Golang. ([Demo](http://wide.b3log.org/signup)) `Apache-2.0` `Go`
-- [Zalenium](https://github.com/zalando/zalenium) - Allows anyone to have a disposable and flexible Docker-based Selenium Grid infrastructure featuring video recording, live preview and online/offline dashboards. `Apache-2.0` `Java/Shell`
 
 ### Continuous Integration
 
 _See [awesome-sysadmin/Continuous Integration & Continuous Deployment](https://github.com/n1trux/awesome-sysadmin#continuous-integration--continuous-deployment)_
 
+### UX testing
+
+- [Uier](https://github.com/sjoerdvanderhoorn/Uier) - Codeless or low-code User Experience test editing and management using Selenium to perform testing or UI automation. Uier tends to be a free self hostable alternative to Applitools, Endtest, Ghost Inspector, Usetrace, Screenster and many others. `Apache-2.0` `Nodejs`
+- [Selenoid](http://aerokube.com/selenoid/latest/) - Lightweight Selenium hub implementation launching browsers within Docker containers. ([Source Code](https://github.com/aerokube/selenoid)) `Apache-2.0` `Go`
+- [Zalenium](https://github.com/zalando/zalenium) - Allows anyone to have a disposable and flexible Docker-based Selenium Grid infrastructure featuring video recording, live preview and online/offline dashboards. `Apache-2.0` `Java/Shell`
+
 ### FaaS/Serverless
 
 *[Serverless computing on Wikipedia](https://en.wikipedia.org/wiki/Serverless_computing)*