add design doc

[FZ2000]

Description

Add design doc for a Neural Network based barrel segmentation algorithm.

This PR does the following:

• Add design doc

Fixes #651

[matthewhannay567]

Some questions:

• Where are you going to get the training data for the CNN? How are you going to train this CNN?
• What exactly is the CNN going to output?
• How will the CNN handle multiple barrels in the same image? A barrel that is slightly obfuscated?

[matthewhannay567]

Can we get an update?