last half of converting to custom exceptions for #75
last half of converting to custom exceptions for #75

soerennielsen/canopy,JeremyBellows/canopy,lefthandedgoat/canopy,skalinets/canopy,lefthandedgoat/canopy,skalinets/canopy,velyo/canopy,pedro-ramirez-suarez/canopy,blair55/canopy,bfrierson/canopy,skalinets/canopy,blair55/canopy,pedro-ramirez-suarez/canopy,GaryGwynn/canopy,velyo/canopy,soerennielsen/canopy,soerennielsen/canopy,blair55/canopy,GaryGwynn/canopy,bfrierson/canopy,skalinets/canopy,somnuk-wk/canopy,blair55/canopy,somnuk-wk/canopy,lefthandedgoat/canopy,JeremyBellows/canopy,soerennielsen/canopy,lefthandedgoat/canopy,JeremyBellows/canopy,JeremyBellows/canopy,skalinets/canopy,JeremyBellows/canopy,lefthandedgoat/canopy