gen: Rename all jOri to jOrigin
gen: Rename all jOri to jOrigin

I keep forgetting what Ori means. I know Go likes to keep short variable
names, but there's got to be a balance we can strike, and especially
since I keep thinking of the "Or Immediate" assembly instruction

robphoenix/exercism-go,exercism/xgo,robphoenix/exercism-go,exercism/xgo,leenipper/xgo,leenipper/xgo