datagrid - editable list fields

added editable list fields

- [x] finish the code
- [ ] gather feedback for my changes
- [ ] submit changes to the documentation


| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| Tests pass?   | none
| Fixed tickets | none
| Doc           | none

- Changes in API "options.tableHead" is now "options.columns" and added an "editable" flag in the options!