Merge pull request #206 from ideasrule/master

Adding pledge for PLATON

Author: takluyver

_sections/30-projects.md

@@ -73,6 +73,7 @@ These projects pledge to drop Python 2 support in or before 2020.
 - [![](assets/biobuilds.png)BioBuilds](https://www.biobuilds.org/)
 - [![](assets/freud.png)freud](https://github.com/glotzerlab/freud)
 - [![](assets/signac.png)signac](https://signac.io)
+- [![](assets/platon.png)PLATON](https://github.com/ideasrule/platon)
 
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