arangojs 7.0.0

[pluma]

This is the WIP PR for the next semver major release.

As a semver major release this includes a number of breaking changes, including:

• dropping support for ArangoDB 2.x (EOL)
• dropping support for Node 6/8 (current LTS is 10/12)
• removing the non-graph API methods from graph collections (the underlying collections can now be accessed via a collection attribute)
• removing the createXYZIndex helper methods as the equivalent JS APIs in ArangoDB have been deprecated for a long time
• EdgeCollection and DocumentCollection have been merged but still exist as separate interfaces for TypeScript
• passing a document ID or a document with an ID from a different collection to a collection method now throws an error (fixes Collection methods that expect document keys should not accept IDs #607)
• collection.list() now returns an ArrayCursor as it should (fixes async collection.list() not using arraycursor #603)

Additionally:

• drastically improving TypeScript type coverage (fixes better type information (typescript) #620)
• documentation inlined into type definition & generated with typedoc
• adding support for options objects wherever they should be allowed (fixes VertexCollection update opts #610)
• adding support for returnNew/returnOld in graph collections (metadata is now returned in the edge/vertex attribute as in the HTTP API) (the new/old attributes as well as the content of the edge/vertex attribute are now merged into the response body for compatibility with the regular collection method return types)
• adding collection.documentId() from ArangoDB JS API (fixes Collection name / ID generator #591)
• all collection (not graph collection) methods that can take either a document or an array of documents now have two versions (e.g. update and updateAll) (fixes <collection>.remove() with array of keys or documents #349)
• Database, Collection, Graph, View and Analyzer are memoized now (per-database, or per-connection in the case of Database itself) to avoid multiple objects being created for the same thing

What's currently missing:

• Inline documentation
  • Collection/DocumentManipulation.md
  • Collection/EdgeCollection.md
  • Collection/Indexes.md
  • Collection/SimpleQueries.md
  • Graph/README.md
  • Graph/EdgeCollection.md
  • Graph/Edges.md
  • Graph/VertexCollection.md
  • Graph/Vertices.md
  • Analyzer.md
  • Aql.md
  • Cursor.md
  • Route.md
  • Transaction.md
  • View.md
• Check for any stray TODOs
• Add workflow for generating & publishing typedoc docs via gh-pages
• Double-check return types
• Double-check documentation