check if field exists before deleting, refs https://github.com/stephenmcd/cartridge/issues/17
check if field exists before deleting, refs https://github.com/stephenmcd/cartridge/issues/17

Parisson/cartridge,syaiful6/cartridge,stephenmcd/cartridge,wbtuomela/cartridge,traxxas/cartridge,dsanders11/cartridge,Parisson/cartridge,ryneeverett/cartridge,traxxas/cartridge,ryneeverett/cartridge,wyzex/cartridge,viaregio/cartridge,jaywink/cartridge-reservable,wyzex/cartridge,traxxas/cartridge,stephenmcd/cartridge,syaiful6/cartridge,syaiful6/cartridge,ryneeverett/cartridge,wbtuomela/cartridge,dsanders11/cartridge,Kniyl/cartridge,stephenmcd/cartridge,Kniyl/cartridge,jaywink/cartridge-reservable,viaregio/cartridge,dsanders11/cartridge,Kniyl/cartridge,jaywink/cartridge-reservable,Parisson/cartridge,wyzex/cartridge,wbtuomela/cartridge