New route parameter

/v1/trackers/{id}/artifacts?query  GET

 The "query" parameter will be a URL-encoded JSON object. E.g.

{"field1_id" : "field1_value", "field2_id" : {"operator" : "OR", "value" : ["v1", "v2"]}, "field3_id" : {"operator" : "<", "value" : "field3_value"}}

field_id can be either the ID of the field or the shortname of the field. In the event that the shortname is a number, e.g. 123, then Tuleap will search for field with ID 123 THEN field with shortname 123 if not found.

There are two ways of specifying the field value:

• by providing a direct value; the operator is then assumed to be "="
• by providing an object. That object must provide the properties "value" and "operator"

The value formats are all those that are used with fields

There is also a "values" parameter as for /tracker_reports/:id route