simultaneous processing support with provided specific chunk size

[metasmile]

request 1~5 + chunk size 3 job1 start job2 start job3 start ... job2 finished job1 finished job3 finished

start next chunk job3 start job4 start .... job4 finished job3 finished

all done.

[Pranoy1c]

this would be great to have for faster processing!! i will donate if you have a place to!