--project-desc should not be a required argument for put-project

Description

[djansen@dev test-project]$ /home/djansen/dev/zanata-platform/client/zanata-cli/target/appassembler/bin/zanata-cli put-project --username djansen --key $KEY --default-project-type file --project-name thing1 --project-slug thing1 --url "http://localhost:8180"
Option "--project-desc" is required

When creating a project via the web ui, the description is an optional field. The client has marked this as "required:true" which contradicts the former.
Simply, if the field is not specified it should not (over)write that data.