Fixed sorting issue for large files

[roberthawdon]

Description

Fixes the sorting of files by size that originally suffered from an integer overflow. #107

Motivation and Context

Fixes issue #107

How Has This Been Tested?

Yes

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.