Refactor to use accessor and setting specs
Refactor to use accessor and setting specs

- added accessor spec
- added additional settings
- fixed bug to allow creation of table with all properties when columns
  attribute not specified

karger/exhibit,simile-widgets/exhibit,simile-widgets/exhibit,cdenise/exhibit,cdenise/exhibit,cdenise/exhibit,cdenise/exhibit,karger/exhibit,karger/exhibit,simile-widgets/exhibit,karger/exhibit,simile-widgets/exhibit