Soft mapping of Las data to osdu wellbore and welllog objects

Currently the mapping from las files to osdu objects is hard coded. This needs to be soft coded in order to support custom headers.

Data mappings should be read from file and look something like this:

{
   "kind": "osdu:wks:work-product-component--WellLog:1.1.0",
   "mapping":
    {
        "acl.viewers": "CONFIG.data_default_viewers",
        "acl.owners": "CONFIG.data_default_owners",
        "legal.legaltags": "CONFIG.legal_tags",
        "legal.otherRelevantDataCountries": "CONFIG.legal_relevant_data_countries",
        "legal.status": "CONFIG.legal_status",
        "data.ReferenceCurveID": "las.curves[0].mnemonic",
        "data.WellboreID": {
            "type": "function",
            "function": "get_wellbore_id",
            "args": []
        },
        "data.Curves": {
            "type": "array",
            "source": "las.curves",
            "mapping": {
                "CurveID": "mnemonic",
                "Mnemonic": "mnemonic",
                "CurveUnit": {
                    "type": "function",
                    "function": "las2osdu_curve_uom_converter",
                    "args": [
                        "CONFIG.data_partition_id",
                        "mnemonic"
                    ]
                }        
            }
        }
    }
}

This is an example of how a mapping from LAS to a welllog could be achieved.

Reverse mappings from OSDU to LAS will be considered in a future change.