Add Steven Loria (@sloria) to the contributors list for his documentation on Marshmallow integration.
Add Steven Loria (@sloria) to the contributors list for his documentation on Marshmallow integration.

MuhammadAlkarouri/hug,timothycrosley/hug,timothycrosley/hug,MuhammadAlkarouri/hug,MuhammadAlkarouri/hug,timothycrosley/hug