Fix poor migration performance

• Release v0.1.11 introduced a new migration that moved data from one table to another. This migration was implemented in a non-performant way that resulted in excessive memory usage in production, preventing release.
  This release refactors that code into a more performant SQL query.
• Use the DOI in the citation metadata field for published dandisets.

Remove erroneous swagger path param

Merge pull request #473 from dandi/fix-swagger

Remove incorrect param in swagger doc

Remove AssetMetadata and VersionMetadata tables

Originally we stored Asset and Version metadata in separate tables, AssetMetadata and VersionMetadata. This has made life substantially more difficult, so for simplicity we are moving metadata into the Asset and Version tables.

Fix publish

Publishing was creating new assets instead of updating the existing asset, which is not the behavior specified in the publish design doc. This has been fixed.

#459
#460

API Documentation Improvements

Improves the API docs on the dandi-api Swagger page.

Enable Publish

Enabling publish for the general public

Validation error UX

#417

v0.1.6: Merge pull request #451 from dandi/publish-dois

• Do not allow dandisets with published versions to be deleted
• Add asset metadata view
• Bump dandischema version to 0.3.2
• Add setting for publishing DOIs as "findable"

assetsSummary Optimization

Turns out that the assetsSummary calculation was taking a long time
because each asset metadata was being fetched from the DB separately, so
a Version with 1000 assets meant 1000 SQL queries. This select_related
call should roll them up into a single large query, which cuts down on
network traffic.

This should resolve error 503/409 occurring during upload.

Publish Features

• Do not allow republishing a dandiset without modifying it. This prevents users from accidentally creating multiple identical versions.
• Write dandiset.jsonld, assets.jsonld, and collection.jsonld manifest files.
• Fix a bug where published version still had the manifestLocation of the draft version.
• Add logging for errors encountered while calculating assetsSummary.