CleanData after onChange between oneOf

When you select one of the list from the oneOf and move to un-select, the value is still saved in the container.

For example, select [An object] from the oneOf example and than select [].
When you getData(), the values are still stored in the container.

This kind of situation will mismatch the two function validate() and getData()
For example select [A multiple of 3] and fill with number 10.
The getData() will get the value 10 and the validate() will show error.

However, when you select [] and repeat the two function,
getData() will get the value 10 and validata() will show success.

http://brutusin.org/json-forms/#7

Start with the oneOf example at http://brutusin.org/json-forms/#7 and reproduce the sequence of selecting an option, entering a value, and then selecting []. Compare getData() with validate() after the onChange event; done means deselecting an option removes its stored value and the two functions remain consistent.

Written by the indexing model from the issue text.