Merge pull request #1732 from pints-team/papers

Updated list of papers using PINTS.

Author: MichaelClerx

papers/main-pints.bib

@@ -1,10 +1,10 @@
 @article{Clerx2019Pints,
   title={Probabilistic Inference on Noisy Time Series ({PINTS})},
   author={Clerx, Michael and Robinson, Martin and Lambert, Ben and Lei, Chon Lok and Ghosh, Sanmitra and Mirams, Gary R and Gavaghan, David J},
+  year={2019},
   journal={Journal of Open Research Software},
   volume={7},
   number={1},
   pages={23},
-  year={2019},
   doi={10.5334/jors.252}
 }