Invalid prop type color supplied to startElement In [Button]

[DevYuns]

Describe the bug
When I add Image component directly into startElement, An error occurred like below.

  Warning: Failed prop type: Invalid props.style key `color` supplied to `Image`.
  Bad object: {
    "color": "#FFF"
  }

I think that cloneElement in this line makes a problem. Since color prop is not supported in <Image/>.

To Reproduce
Steps to reproduce the behavior:

Add <Image/> component directly into startElement in [Button]`

<Button
  startElement={<Image source={IC_MASK} />}
  text={getString('LOGIN')}
/>

Additional context

To fix this problem temporality, Wrap Image component with View.

<Button
  startElement={
    <View>
       <Image source={IC_MASK} />
    </View>
   }
  loading={isLoggingIn}
  text={getString('LOGIN')}
/>

[hyochan]

Closes #252