Add test for tabular output of rate counters.
Add test for tabular output of rate counters.

efcs/benchmark,google/benchmark,everbase/benchmark,everbase/benchmark,mockingbirdnest/benchmark,mockingbirdnest/benchmark,google/benchmark,efcs/benchmark,mockingbirdnest/benchmark,google/benchmark,mockingbirdnest/benchmark,disconnect3d/benchmark,everbase/benchmark,codygray/benchmark,codygray/benchmark,efcs/benchmark,disconnect3d/benchmark,efcs/benchmark,everbase/benchmark,codygray/benchmark,codygray/benchmark,disconnect3d/benchmark,disconnect3d/benchmark