Add pipeline status to readme.

README.md

 # P³LS³
 **P**redictable **P**arallel **P**atterns **L**ibrary for **S**calable **S**mart **S**ystems
 
+Master Branch: [![pipeline status](http://lab.las3.de/gitlab/las3/development/scheduling/predictable_parallel_patterns/badges/master/pipeline.svg)](http://lab.las3.de/gitlab/las3/development/scheduling/predictable_parallel_patterns/commits/master)
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 ## Project Structure
 
 The project uses [CMAKE](https://cmake.org/) as it's build system,
@@ -39,4 +42,4 @@ Please regularly test with thread sanitizer enabled and make sure to not
 keep the repository in a state where the sanitizer reports errors.
 
 Consider reading [the section on common data races](https://github.com/google/sanitizers/wiki/ThreadSanitizerPopularDataRaces)
-to get an idea of what we try to avoid in our code.
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+to get an idea of what we try to avoid in our code.