comment + change in error values + checks
comment + change in error values + checks

* adding some comment to explain the weirdness of traject time parsing
* changing default value for reliability to 0
    if it fails, it will return traject_time => 'unknown'
    and reliability => '0'
* adding a check at the end of the parsing to ensure that it
got coherent data

kakwa/sytadin-scraper