app: add dummy client/README.md
model: prompt for the model name
datasource: prompt for the datasource name
model: show connector names in list of datasources
property: support typed array

Add a prompt for item type when the array was selected as the property
type.
model: ask for the plural form
acl: remove "property" from the list of scopes

Property-based access-control is not implemented by loopback yet.
Merge pull request #15 from strongloop/feature/add-dummy-client

UX improvements