Added a set default displayname method to the users schema.
Added a set default displayname method to the users schema.

mjmostachetti/grasshopper-core-nodejs,Solid-Interactive/grasshopper-core-nodejs,grasshopper-cms/grasshopper-core-nodejs,Solid-Interactive/grasshopper-core-nodejs,grasshopper-cms/grasshopper-core-nodejs,mjmostachetti/grasshopper-core-nodejs