Redesign config file structure

[chuwy]

Goals:

• Consistency with the rest of estate
• Removing unused or deprecated properties (hardcodec credentials, type as NSQ support is removed Drop NSQ support #211, bucketPartitioned)
• Future-proofing for upcoming features

Examples:

{
        "region": "eu-central-1",
        "purpose": "raw",

        "input": {
            "appName": "acme-s3-loader",
            "streamName": "enriched-events",
            "position": "LATEST",
            "maxRecords": 10
        },

        "output": {
            "s3": {
                "path": "s3://acme-s3-bucket/subdir/",
                "dateFormat": "%Y-%M-%d",
                "filenamePrefix": "pre",
                "maxTimeout": 2000,
                "format": "gzip"
            },

            "badStreamName": "s3-loader-bad"
        },

        "buffer": {
            "byteLimit": 2048,
            "recordLimit": 10,
            "timeLimit": 5000
        },

        "monitoring": {
            "snowplow": {
                "host": "http://snplow.acme.ru",
                "port": 80,
                "appId": "angry-birds",
                "method": "POST"
            },
        }
    }