WIP refactoring code bomb:
- Do not use CGI in process_bug.cgi
- Use the same type INT4 for all ID fields
- Store all single-select fields as IDs, not as names in bugs table
Update old DB update code - new DB initialises correctly now
Remove --- used as NULL surrogate
Remove duplicate get_legal_field_values() API
Add nullable property for fields
Remove CGI usage in editvalues.cgi
Move "custom" templates to "default"
Move fieldvaluecontrol generation into a separate procedure
Return target_milestone and version validators back
Delete duplicate bug.choices API and duplicate 'select' block
Make Object::set() public
Remove CGI usage in show_bug.cgi
Convert value ids to names on the bug form (ugly, but already works)
Refactor field create/edit templates, allow to edit nullable property
Fix entry (use value names in create.html.tmpl)
Fix multiselects
Fix search on multiselect fields
Bugzilla::Bug code style
Do not return blessed error_self
Fix "Edit Multiple", use bug/field template for all select fields in it