sql/pgwire: Add benchmarks for each writeBuffer operation
sql/pgwire: Add benchmarks for each writeBuffer operation

glycerine/cockroach,paperstreet/cockroach,maxlang/cockroach,vaibhavarora/cockroach,petermattis/cockroach,petermattis/cockroach,petermattis/cockroach,maxlang/cockroach,veteranlu/cockroach,veteranlu/cockroach,maxlang/cockroach,maxlang/cockroach,paperstreet/cockroach,vaibhavarora/cockroach,glycerine/cockroach,vaibhavarora/cockroach,glycerine/cockroach,glycerine/cockroach,paperstreet/cockroach,glycerine/cockroach,maxlang/cockroach,vaibhavarora/cockroach,paperstreet/cockroach,veteranlu/cockroach,veteranlu/cockroach,vaibhavarora/cockroach,vaibhavarora/cockroach,paperstreet/cockroach,petermattis/cockroach,paperstreet/cockroach,maxlang/cockroach,petermattis/cockroach,glycerine/cockroach,maxlang/cockroach,veteranlu/cockroach,petermattis/cockroach,vaibhavarora/cockroach,paperstreet/cockroach,glycerine/cockroach,petermattis/cockroach,veteranlu/cockroach,vaibhavarora/cockroach,glycerine/cockroach,veteranlu/cockroach,veteranlu/cockroach,paperstreet/cockroach,maxlang/cockroach,petermattis/cockroach