* Add listing sites, goals and custom props to Sites API

* Rename exmaple props in tests

* Rename `allowed_custom_props` -> `custom_properties`

* Expose goal name in GET endpoints for goals in Sites API

* Bump default pagination limit to 100 and max to 1000

* Introduce Goal.name/display_name and use the first one for name in API

* Extend goal list response but hide currency

* Settle on `display_name` instead of `name`

* Allow viewer members to get site details and list site goals

* Don't include currency in goal's display name