Allow board delete via UI

ref #16

internal/repository/storm/board.go

@@ -61,6 +61,18 @@ func (r *BoardRepository) Save(board *repository.Board) error {
 }
 
 func (r *BoardRepository) Delete(id repository.BoardID) error {
+	b := &boardItem{
+		ID: string(id),
+	}
+
+	if err := r.db.DeleteStruct(b); err != nil {
+		if err == storm.ErrNotFound {
+			return repository.ErrNotFound
+		}
+
+		return errors.Wrapf(err, "could not delete board '%s'", id)
+	}
+
 	return nil
 }