added connections alias and doc count in status api.

[naveenpajjuri]

Description

Added few more fields in status api useful for publishing metrics to cloudwatch.

New response :

syncing phase:

{
    "status": "SYNCING",
    "connection_alias": "source",
    "leader_index": "check6",
    "follower_index": "folcheck6",
    "replication_data": [
        {
            "shard_id": "[folcheck6][0]",
            "doc_count": 1,
            "syncing_task_details": {
                "remote_checkpoint": 0,
                "local_checkpoint": 0,
                "seq_no": 1
            }
        },
        {
            "shard_id": "[folcheck6][1]",
            "doc_count": 1,
            "syncing_task_details": {
                "remote_checkpoint": 0,
                "local_checkpoint": 0,
                "seq_no": 1
            }
        }
    ]
}

Bootstrap phase :

{
    "status": "BOOTSTRAPPING",
    "connection_alias": "source",
    "leader_index": "check6",
    "follower_index": "folcheck6",
    "replication_data": [
        {
            "shard_id": "[folcheck6][0]",
            "doc_count": 0,
            "bootstrap_task_details": {
                "bytes_total": 208,
                "bytes_recovered": 208,
                "bytes_percent": 100.0,
                "files_total": 1,
                "files_recovered": 1,
                "files_percent": 100.0,
                "start_time": 1625138711361,
                "running_time": 177
            }
        },
        {
            "shard_id": "[folcheck6][1]",
            "doc_count": 0,
            "bootstrap_task_details": {
                "bytes_total": 208,
                "bytes_recovered": 208,
                "bytes_percent": 100.0,
                "files_total": 1,
                "files_recovered": 1,
                "files_percent": 100.0,
                "start_time": 1625138711350,
                "running_time": 203
            }
        }
    ]
}```


 
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[tbhanu-amzn]

lgtm