Generate slices of method *Sig(nature)s instead of linked lists.
Remove custom lsort function in favor of sort.Interface.
Eliminates another use of stringsCompare.
Passes go build -a -toolexec 'toolstash -cmp' std cmd.
Change-Id: I9ed1664b7f55be9e967dd7196e396a76f6ea3422
Reviewed-on: https://go-review.googlesource.com/14559
Reviewed-by: Dave Cheney <dave@cheney.net>
