improve performance of bookmark file import

[WileESpaghetti]

The speed of importing from an HTML bookmark file could be improved. We currently import/process bookmarks one by one and could probably speed things up by using bulk actions.

We need to be careful to make sure that events fire properly when switching to bulk processing

[WileESpaghetti]

There were a couple of good tips from the video Building an Efficient ETL Process with Laravel. Other good advice about Laravel job optimization is found here.

• only put what is needed in the job constructor
  • When restoring a job all relationships from models in the constructor are eagerly loaded which might load data that isn't needed
• the flatter you can make data generally the better for ETL.
• don't do work if you don't have to
  • writes are more expensive than reads, so if a read can prevent a write then an extra read query might be worth it
• see if you can benefit from indexes
  • index on foreign keys can help when there is a large amounts of data