Add new config In aggregation

[wzquyin]

When we use aggregate builder ,the script start with
use databasename;

dbk_agg.sampleSize = 100;
dbk_agg.useLimitSample= true;
...

then run the script,show the result

but the results count limit by mongo shell DBQuery.shellBatchSize

can you add a new set at start stage ,just like sampleSize to set the mongoshell limit ?

some times we know the result count like $group...and we can use export csv to save the result.