Add Apollo assembly and feature importing status to JBrowse 2 jobs widget

[garrettjstevens]

Show upload and parsing status of assembly and/or features in the JBrowse job manager so that users can easily see the status of their data uploading.

The first step is to see if jobs can be added to the jobs widget without needing to use the JBrowse job manager. If it turns out the jobs would benefit from being queued (e.g. they are using more local system resources than expected), then see if we can use the job manager.