Resolving maximum call stack size exceeded issue

[MGardner02]

This is a fix for #26 which seems to occur when too much data is queued up at once and then return using the recursive call. We saw the error coming up when reading files with millions of lines and when pulling thousands of results from a DB. I updated the code to follow the same logic as before, but use a loop instead to avoid recursion issues.

I read through another thread and saw this was discussed as a potential solution, the update passed all unit testing and worked well when I tested against a few additional stream examples. Let me know your thoughts.

[dominictarr]

sorry, I no longer have access to merge and publish changes to this module. You'll need to publish this as map-stream2 (or whatever you choose) and maintain it yourself)