Rephrase testID docs to be more generic instad of focused on detox

Author: Maurice Döpke

README.md

@@ -518,7 +518,7 @@ If true, the user won't be able to interact with the view.
 
 #### `testID` (`optional`)
 
-Used to test your app with tools like e.g. detox.
+Usually used by app automation frameworks.
 Fully supported on iOS. On Android, only supported for `mode="date"`.
 
 ```js

src/datepicker.android.js

@@ -22,7 +22,7 @@ export default class DatePickerAndroid {
    *   - `value` (`Date` object) - date to show by default
    *   - `minimumDate` (`Date` object) - minimum date that can be selected
    *   - `maximumDate` (`Date` object) - maximum date that can be selected
-   *   - `testID` (`string`) - testID for usage with e.g. detox
+   *   - `testID` (`string`) - Sets view tag for use with automation frameworks
    *   - `display` (`enum('calendar', 'spinner', 'default')`) - To set the date-picker display to calendar/spinner/default
    *     - 'calendar': Show a date picker in calendar mode.
    *     - 'spinner': Show a date picker in spinner mode.