Adding capability to take max upload size per request.

[nucleussoftwareopen]

As of now FileUploadBase has sizeMax which is global for all uploads, in many cases it is required to calculate this limit based on request.

https://stackoverflow.com/questions/16585866/changing-file-size-limit-maxuploadsize-depending-on-the-controller

[jochenw]

Hi, thanks for the PR. I'd like to understand, what this is about, or in other words: What is the use case?

In my opinion, if there really is a request, that needs special handling: Why not just create another controller?

Thanks,

Jochen

[garydgregory]

-1, there should be tests along with new features.

[jochenw]

A valid point, Gary, I'll keep that in mind. Besides: Please, rebase.

[nucleussoftwareopen]

Hi, Thanks for sharing your thoughts & reviews.
In this PR we are introducing a new functionality which allows a user to get the allowed max size for current file upload. Also, the subclasses can override the newly introduced getSizeMaxForThisRequest() method to calculate the allowed size per request.
This will help users to provide granularity in the allowed max size for the files uploaded via different requests against different requirements/ use-cases.