Add test to remove duplicates when case insensitive.
Add test to remove duplicates when case insensitive.

bj7/lime-backend,ch1bo/lime-backend,ch1bo/lime-backend,limetext/lime-backend,bj7/lime-backend,bj7/lime-backend,ch1bo/lime-backend,limetext/lime-backend,codex8/lime-backend,codex8/lime-backend,bj7/lime-backend,ch1bo/lime-backend,limetext/lime-backend,codex8/lime-backend,limetext/lime-backend,codex8/lime-backend,limetext/backend