Updating the library to Python 3

[Navdevl]

The PR has the following set of improvements.

1. Since Python 2 sunset date is crossed for a while, this PR moved the parts of functionalities using Py3 related ones.
2. Pickle loaded and dumped the sample files to use Py3 based approach.
3. Added an output.json file for the other people to easily understand what kind of outputs CVScan provides out of the box by default. (Yes, obviously it can be extended further)
4. Closes issue #23

What this PR isn't? This PR didn't fix any of those existing PEP8 issues because for the following reason.

1. The diff will be too much and will not be easy for the reviewer as to understand how much of the code is added/removed/moved.
2. Plus, the PR's focus is to Port to Py3 soon and worked solely on that part alone.

Signed-off-by: Naveen Honest Raj K [email protected]

[Navdevl]

@imkarthikk @swaathi If this PR sounds good to merge, can we please try to move this? I have OCD for pending pull requests or any pending items. Hehe. 😅😅