update issues with primary keys === '0'
update issues with primary keys === '0'

WIP -
    test rest for ASC, ORDERBY... custom callback logic
    Use self::column consts rather than string names in rest
    Document rest.

RichardTMiles/CarbonPHP,RichardTMiles/CarbonPHP,RichardTMiles/CarbonPHP,RichardTMiles/CarbonPHP,RichardTMiles/CarbonPHP