[feat] experiment conf json "custom" section should provide a slot "name" for the naming of each configuration

[suzannejin]

The naming of each config will be used at the analysis step and help the user to understand what are the things that are visualized. Something like:

{
    "experiment": "DnaToFloatExperiment",
    "custom": [
        {
            "name": "only_reverse",
            "transform": [
                {
                    "column_name": "dna:input:dna",
                    "name": "ReverseComplement",
                    "params": {}
                }
            ]
        },
        {
            "name": "reverse_and_noise",
            "transform": [
                {
                    "column_name": "dna:input:dna",
                    "name": "ReverseComplement",
                    "params": {}
                },
                {
                    "column_name": "dna:input:dna",
                    "name": "UniformTextMasker",
                    "params": {
                        "probability": 0.1
                    }
                }
            ]
        }

[mathysgrapotte]

json should be replaced by yaml