[DRAFT] Plugins SHA

[adamkirkwood]

Problem

currently there are around 240 plugins in the registry that do not have releases.
These plugins can not be updated since the update/compare endpoints only check releases.

References:

• https://github.com/adamkirkwood/sketchpacks.api/issues/61

Iteration 1

• plugins reducer stores plugin.sha
• plugin.sha is stored in the sketchpack when plugin.has_versions is false
• updating plugins calls /v1/plugins/:identifier/download/:ref (ref = sha || version)
• exclude plugins locked with a sha from auto-updates
• plugins locked with a sha appear in Library/Updates; manual updating only
• plugins locked with a sha appear in Library/Managed
  • hide lock
  • Latest Version info displays sha