Initial commit
Unnecessary imports removed
Python module renamed.
Minimal kanban board implemented.

 * Board configuration and data stored to wiki page
 * Card can be dragged within columns (board data changes) and between columns (board data and ticket status changes)
 * Users without WIKI_MODIFY and TICKET_MODIFY permissions see read-only board
Card placeholder enabled.
Maintain ticket order in fix_ticket_columns method.
Ticket details dialog added.
jQuery UI theme updated.
Creation and modification times added to ticket dialog.
Missing file added.
Use pointer cursor with cards.
Small style and layout changes.
Board title removed.
Enable summary, priority and type modifications from ticket details dialog.
Use Trac utility function in time conversions.
Ticket details related changes.

 * Client-side objects created with knockout.mapping plugin.
 * Saved board data (i.e columns) wrapped inside object.
 * Full ticket data returned from backend only when explicitly
   requested (for example when ticket detail dialog opens).
 * All ticket fields shown in detail dialog (needs more work on
   layouts and updating).
 * Times now represented as millisecond timestamps in rest api and
   in client-side models.
Data updating fixed.
Enabled ticket status changing from detail dialog.
Ticket detail dialog style tweaked.
All ticket fields editable from detail dialog.