change node shape based on access type.

[emmyoop]

resolves #378

Description

Here's what I came up with with the help of @dbeatty10

access: protected - nothing custom - stays the rounded corner rectangle. This allows the DAG to visually remain exactly the same until groups/access are added to a project
access: public - ellipse shape - This really distinguishes the public nodes that will be accessible outside the project
access: private - sharp cornered rectangle

node	access
raw_people_list	no access defined explicitly
second-model-private	access: private
second-model-public	access: public
top-model	access: protected

Checklist

• I have read the contributing guide and understand what's expected of me
• I have signed the CLA
• I have run this code in development and it appears to resolve the stated issue
• I have opened an issue to add/update docs, or docs changes are not required/relevant for this PR
• I have run changie new to create a changelog entry