adding long description into .shed.yml due to linting issue

tools/mmuphin/.shed.yml

@@ -1,6 +1,9 @@
 name: mmuphin
 owner: iuc
 description: "MMUPHin is an R package implementing meta-analysis methods for microbial community profiles"
+long_description: 
+MMUPHin enables the normalization and combination of multiple microbial community studies. It can then help in identifying microbes, genes, or pathways that are differential with respect to combined phenotypes. 
+Finally, it can find clusters or gradients of sample types that reproduce consistently among studies.
 homepage_url: https://huttenhower.sph.harvard.edu/mmuphin
 remote_repository_url: https://github.com/biobakery/MMUPHin
 type: unrestricted