---++  GET /api/instance/summary/:entity-type/:entity-name
   * <a href="#Description">Description</a>
   * <a href="#Parameters">Parameters</a>
   * <a href="#Results">Results</a>
   * <a href="#Examples">Examples</a>

---++ Description
Get summary of instance/instances of an entity.

---++ Parameters
   * :entity-type Valid options are feed or process.
   * :entity-name Name of the entity.
   * start <optional param> Show instances from this date. Date format is yyyy-MM-dd'T'HH:mm'Z'.
       * By default, it is set to (end - (10 * entityFrequency)).
   * end <optional param> Show instances up to this date. Date format is yyyy-MM-dd'T'HH:mm'Z'.
       * Default is set to now.
   * colo <optional param> Colo on which the query should be run.
   * lifecycle <optional param> Valid lifecycles for feed are Eviction/Replication(default) and for process is Execution(default).
   * filterBy <optional param>  Filter results by list of field:value pairs.
   Example1: filterBy=STATUS:RUNNING,CLUSTER:primary-cluster
   Example2: filterBy=Status:RUNNING,Status:KILLED
       * Supported filter fields are STATUS, CLUSTER
       * Query will do an AND among filterBy fields.
   * orderBy <optional param> Field by which results should be ordered.
       * Supports ordering by "cluster".
   * sortOrder <optional param> Valid options are "asc" and "desc"
   Example: orderBy=cluster sortOrder=asc
   * doAs <optional query param> allows the current user to impersonate the user passed in doAs when interacting with the Falcon system.

---++ Results
Summary of the instances over the specified time range

---++ Examples
---+++ Rest Call
<verbatim>
GET http://localhost:15000/api/instance/summary/process/WordCount?colo=*&start=2014-01-21T13:00Z&end=2014-01-21T16:00Z
</verbatim>
---+++ Result
<verbatim>
{
    "status":"SUCCEEDED",
    "message":"default/SUMMARY\n",
    "requestId":"default/c344567b-da73-44d5-bcd4-bf456524934c\n",
    "instancesSummary":
        {
            "cluster":"local",
            "map":
                {
                    "entry":
                        {
                            "key":"SUCCEEDED",
                            "value":"value"
                         }
                }
            }
        }
}
</verbatim>

---+++ Rest Call
<verbatim>
GET https://localhost:16443/api/instance/summary/process/WordCount?filterBy=Status:KILLED,Status:RUNNING&start=2015-06-24T16:00Z&end=2015-06-24T23:00Z&colo=*
</verbatim>
---+++ Result
<verbatim>
{
    "status":"SUCCEEDED",
    "message":"local/SUMMARY\n",
    "requestId":"local/1246061948@qtp-1059149611-5 - 34d8c3bb-f461-4fd5-87cd-402c9c6b1ed2\n",
    "instancesSummary":[
        {
            "cluster":"local",
            "map":{
                "entry":{
                    "key":"RUNNING",
                    "value":"1"
                },
                "entry":{
                    "key":"KILLED",
                    "value":"1"
                }
            }
        }
    ]
}
</verbatim>

---+++ Rest Call
<verbatim>
GET https://localhost:16443/api/instance/summary/process/WordCount?orderBy=cluster&sortOrder=asc&start=2015-06-24T16:00Z&end=2015-06-24T23:00Z&colo=*&doAs=joe
</verbatim>
---+++ Result
<verbatim>
{
    "status":"SUCCEEDED",
    "message":"local/SUMMARY\n",
    "requestId":"local/1246061948@qtp-1059149611-5 - 42e2040d-6b6e-4bfd-a090-83db5ed1a429\n",
    "instancesSummary":[
        {
            "cluster":"local",
            "map":{
                "entry":{
                    "key":"SUCCEEDED",
                    "value":"6"
                },
                "entry":{
                    "key":"KILLED",
                    "value":"1"
                }
            }
        }
    ]
}
</verbatim>