domainlist: Optimized it a bit more by not making a new slice in goBackToStartOfLine.  Maybe 10% improvement.
domainlist: Thought about it a little bit and realized the condition should be offset <= 80, not offset < 80.
Thought about the goBackToStartOfLine harder and I think I fixed it.  But I should really make a rigorous test for it.
The benchmarks are not enough.