For some reason, provided UTC timestamp does not comply ISO8601, as its
format is YYYY-DD-MM instead of expected YYYY-MM-DD.

This can be checked with the also provided "text" field of
emission date object. Example:
"data_emissio": {
            "text": "14/05/2002�21:39",
            "utc": "2002-14-05T21:39:28+0200"
}

This commit fixes this behavior.

Added test is one of the cases of broken compatibility.
Issue is in featuring multiple languages in the subtitles field.

CCMA extractor used to raise an exception when attempting the download of
a URL featuring multiple languages in the subtitles.

When a single language is available, the field is the expected dict.
When multiple languages are available, a list of dicts is provided.

This commit fixes this issue.