Feature/meta graph: counts rm

[bwalsh]

This PR adds commands to meta flat. Note: the rm command removes all project content from the graph

• query sheepdog meta graph counts

 aced_submission meta graph counts --format json | jq -rc '.[] | select(.project_id == "aced-Alzheimers") | [.table, .count]'
["node_researchstudy",1]
["node_patient",287]
["node_researchsubject",287]
["node_specimen",75]
["node_observation",192086]
["node_condition",4311]
["node_medicationadministration",199]
["node_documentreference",730]
["node_task",75]

• delete project contents from sheepdog meta graph rm

  
  # aced_submission meta graph rm --project_id aced-Alzheimers

• count: 0 project_id: aced-Alzheimers table: node_familymemberhistory

• count: 75 project_id: aced-Alzheimers table: node_task

• count: 730 project_id: aced-Alzheimers table: node_documentreference

• count: 199 project_id: aced-Alzheimers table: node_medicationadministration

• count: 0 project_id: aced-Alzheimers table: node_medication

• count: 4311 project_id: aced-Alzheimers table: node_condition

• count: 192086 project_id: aced-Alzheimers table: node_observation

• count: 75 project_id: aced-Alzheimers table: node_specimen

• count: 0 project_id: aced-Alzheimers table: node_substance

• count: 287 project_id: aced-Alzheimers table: node_researchsubject

• count: 287 project_id: aced-Alzheimers table: node_patient

• count: 1 project_id: aced-Alzheimers table: node_researchstudy

• count: 1 project_id: Alzheimers table: node_project

• re-query

  aced_submission meta graph counts --format json | jq -rc '.[] | select(.project_id == "aced-Alzheimers") | [.table, .count]'
  >>> nothing returned

• project no longer exists, but is still in arborist resources (expected)

 gen3_util projects ls
...
  /programs/aced/projects/Alzheimers:
    exists: false