Issue assignments

[cdolfi]

Things to note during review:

• opendatahub-io is a good view of this graph (or any repo(s) that consistently do assignments)
• We should consider before turning this query into a materialized view if we want to join on the contributors table to have the login info available off the bat for viewing on a local/private instance
• the conversation on pages will definitely move the location of the graph. This location is temporary until we have a good home for it. I have a few visualizations that are close to done and once those are in lets discuss new page break downs

[cdolfi]

@JamesKunstle Fixed code to make it where the values are how many issues are assigned or unassigned