Refrain from transcoding SBE field names in snake_case

[salsferrazza]

I believe there is an option in the SBE decoding library that snake cases all of the decoded field names, this should be suppressed and default to verbatim transcoding of the field name as specified in the schema.

[mservidio]

@salsferrazza Yes, field names are converted using this:

def convert_to_underscore(name):
    name = name.strip('@').strip('#')
    sub_str = re.sub('(.)([A-Z][a-z]+)', r'\1_\2', name)
    return re.sub('([a-z0-9])([A-Z])', r'\1_\2', sub_str).lower()

However, naming requirements differ per output type. IE: BigQuery won't accept a dash '-' in a column name. So if we considered doing something like this we still need some way to sanitize field names based on the output type requirements.

See: https://cloud.google.com/bigquery/docs/schemas