FEAT: Single / multiple PDF support

[bradleyrule]

Requirement ID: REQ-009

Problem Description

Manually running the program on one PDF at a time is slow and burdensome to the user.

Feature Description

Enable the user to queue up as many PDFs for analysis as they want and process them all without human intervention.

• This could be achieved by running the program on all PDFs within a specific folder, or allowing the user to provide a zip file of the documents they want processed.