Added new split option

[ArbaazKhan1]

closes issue #5100

I brought back some of the old logic from 2.1 for splitting tablets with excessive files. I created a utility class to handle to handle the old batching logic to split the tablets. Withing Tablet I added the logic on if tablets should be split or not.

[kevinrr888]

I'm currently working on #5733 which will have split points be computed in a completely new way. This might make some of these changes obsolete, will just have to figure that out when we come to it.
(nothing to change here now, just adding context)

[ArbaazKhan1]

Okay, we can hold off on this one until #5733 is finished

[kevinrr888]

Okay, we can hold off on this one until #5733 is finished

I wouldn't say we have to hold off, if this looks good then it could be merged in.
I'm just saying one of us will probably need to consider the others changes depending on whichever is merged first.

[keith-turner]

Tablets no longer split int he tablet server, so this change is bringing back code from 2.1 in way that is incorrect and incomplete.