Merge pull request cpp-best-practices#68 from Gluttton/add_GitLab_to_CI

Add GitLab to CI section.

Author: lefticus

02-Use_the_Tools_Available.md

@@ -63,6 +63,10 @@ Continuous Integration (CI) tools automatically build the source code as changes
  * Provides hosted build agents and also allows for user-provided build agents
  * Can be controlled and monitored from within Microsoft Visual Studio
  * On-Premise installation via Microsoft Team Foundation Server
+ * [GitLab](https://gitlab.com)
+ * use custom Docker images, so can be used for C++
+ * has free shared runners
+ * has trivial processing of result of coverage analyze
 
 If you have an open source, publicly-hosted project on GitHub: