Honor *_accessible in User->can_edit_bug
Remove attachments.isurl like in upstream
Remove bugs.keywords column like in upstream
Allow to disable old versions/milestones, rename components.is_active to components.isactive, like in upstream
Add profiles.is_enabled, profiles.last_seen_date columns, like in upstream
Various small schema changes
Fix field editing form, move js out of template
Change field type values for compatibility with upstream
WIP BUG_ID reverse relationships (implementation different to upstream)
Make BUG_ID reverse relationships function

* Show them on the bug form
* Allow to search on them
* Allow to set them in excel import
Hide (search) for multiselects and for bug_id_rev
Remove upstream fielddefs.is_numeric field
Migrate upstream 4.x field_visibility into our fieldvaluecontrol
Move JS from query form template into js/query-form.js
Remove extra <table> around select fields
Do not narrow select fields less than minimum width on hover
Sort legal_values case-insensitively
Use fielddefs.is_mandatory, like in upstream
Show names of non-functional Bug URLs and Keywords types
Fix DB update from 4.4 schema (at least for MySQL)