Fix _fillData for filling an input with the '0' value

In 1.2.0 when you call _fillData with the value '0' for an input field, the field is blanked instead of the value '0'. And a 4 part name in _createPojoFromInput was failing due to the line 858 (d1[parts[2]] = val).
This pull request fix the problem with a generic function that works for all part name.