update CHANGELOG and CONTRIBUTING guide [skip ci]

.github/CONTRIBUTING.md

@@ -15,10 +15,16 @@ is as follows:
 1. Check that there isn't already an issue about your idea in the
    [Sarek issues](https://github.com/SciLifeLab/Sarek/issues) to avoid
    duplicating work.
-    * Feel free to add a new issue here for the same reason.
+    * Feel free to add a [new issue here](https://github.com/SciLifeLab/Sarek/issues/new/choose) for the same reason.
 2. Fork the Sarek repository to your GitHub account
-3. Make the necessary changes / additions within your forked repository
-4. Submit a Pull Request against the `dev` branch and wait for the code to be reviewed and merged.
+3. [Configure a remote for your fork](https://help.github.com/articles/configuring-a-remote-for-a-fork/)
+```
+git remote add upstream https://github.com/SciLifeLab/Sarek.git
+```
+
+4. [Sync your fork](https://help.github.com/articles/syncing-a-fork/)
+5. Make the necessary changes / additions within your forked repository
+6. Submit a [Pull Request](https://github.com/SciLifeLab/Sarek/compare) against the `dev` branch and wait for the code to be reviewed and merged.
 
 If you're not used to this workflow with git, you can start with some [basic docs from GitHub](https://help.github.com/articles/fork-a-repo/) or even their [excellent interactive tutorial](https://try.github.io/).
 

CHANGELOG.md

@@ -21,9 +21,11 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - [#621](https://github.com/SciLifeLab/Sarek/pull/621) - Simplify tests
 - [#627](https://github.com/SciLifeLab/Sarek/pull/627), [#629](https://github.com/SciLifeLab/Sarek/pull/629) - Refactor docs
 - [#629](https://github.com/SciLifeLab/Sarek/pull/629) - Refactor config
+- [#632](https://github.com/SciLifeLab/Sarek/pull/632) - Use 2 threads and 2 cpus FastQC processes
 
 ### `Removed`
 - [#616](https://github.com/SciLifeLab/Sarek/pull/616) - Remove old Issue Template
+- [#629](https://github.com/SciLifeLab/Sarek/pull/629) - Remove old Dockerfiles
 
 ### `Fixed`
 - [#621](https://github.com/SciLifeLab/Sarek/pull/621) - Fix VEP tests