Merge pull request JedWatson#1240 from jihchi/patch-1

[README] Remove duplicated `promptTextCreator` field

README.md

@@ -220,7 +220,6 @@ Property | Type | Description
 `isOptionUnique` | function | Searches for any matching option within the set of options. This function prevents duplicate options from being created. By default this is a basic, case-sensitive comparison of label and value. Expected signature: `({ option: Object, options: Array, labelKey: string, valueKey: string }): boolean` |
 `isValidNewOption` | function | Determines if the current input text represents a valid option. By default any non-empty string will be considered valid. Expected signature: `({ label: string }): boolean` |
 `newOptionCreator` | function | Factory to create new option. Expected signature: `({ label: string, labelKey: string, valueKey: string }): Object` |
-`promptTextCreator` | function | Creates prompt/placeholder option text. Expected signature: `(filterText: string): string`
 `shouldKeyDownEventCreateNewOption` | function | Decides if a keyDown event (eg its `keyCode`) should result in the creation of a new option. ENTER, TAB and comma keys create new options by dfeault. Expected signature: `({ keyCode: number }): boolean` |
 `promptTextCreator` | function | Factory for overriding default option creator prompt label. By default it will read 'Create option "{label}"'. Expected signature: `(label: String): String` |