Refactor how River - Reach is returned in JSON

[ar-siddiqui]

HEC-RAS has the following hierarchical structure for Rivers and Reaches:

{
    "River A": {
       "Reach 1": [
            "Node 1",
            "Node 2",
            "...."
       ],
       "Reach 2": [
            "Node 1",
            "Node 2",
            "...."
        ]       
    },
    "River B": {
        "Reach 1": [
             "Node 1",
             "Node 2",
             "...."
        ],
        "Reach 2": [
            "Node 1",
            "Node 2",
            "...."
        ]
    }
}

Currently, the API doesn't conform to this structured format and returns data like this in index, geospatialdata, forcingdata (forcingdata was done deliberately like this to match the pattern):

{
    "River A - Reach 1": [
        "Node 1",
        "Node 2",
        "...."
    ],
    "River A - Reach 2": [
        "Node 1",
        "Node 2",
        "...."
    ]
}

Fix the API response to match HEC-RAS Structure in

• Index
• GeospatialData
• ForcingData
• Database

This will be a breaking change.