add PySCIPOpt to list (#173)

Author: mattmilten

_sections/30-projects.md

@@ -76,6 +76,7 @@ for some that aren't directly comparable. -->
 -[An Introduction to Applied Bioinformatics](http://readiab.org)
 -[pvlib-python](https://github.com/pvlib/pvlib-python)
 -[QIIME](http://qiime.org)
+-[PySCIPOpt](https://github.com/SCIP-Interfaces/PySCIPOpt)
 -[SPADE](https://github.com/javipalanca/spade)
 -[gala](https://gala.readthedocs.io)
 -[CIS](https://github.com/cedadev/cis)