Update ReferenceProperty to generate subKey as a string to avoid errors where model shave to ID.
QBug: Add a bunch of missing context setup.
QBug: Add missing subtype for QIssueComment.issueId
Fix subWindow context not having the correct parent.
Make autocomplete popup have a max height and be scrollable.  Still needs some work with dismissing the popup.
QBug: Update SchemaImport to use ReferenceArrayProperty for reference arrays.
Merge branch 'master' of https://github.com/foam-framework/foam