Ability to define button custom class

[martyan]

Hi folks, it would be nice to be able to define custom class for each button. I know you can define inline styles, but classes are more concise and organized IMO.

{
  text: 'reply',
  onPress:() => console.log('reply'),
  style: { backgroundColor: 'orange', color: 'white' },
  cls: 'custom-class-1'
}

[coveralls]

Coverage remained the same at 91.327% when pulling 03e5d96 on martyan:master into 02faa3c on react-component:master.

[silentcloud]

@martyan className may be better

[martyan]

@silentcloud I wanted to keep uniformity as there is already prefixCls used for className prefix.

Updated to use className.

[coveralls]

Coverage remained the same at 91.327% when pulling 4b08f42 on martyan:master into 02faa3c on react-component:master.

[coveralls]

Coverage remained the same at 91.327% when pulling 4b08f42 on martyan:master into 02faa3c on react-component:master.

[coveralls]

Coverage remained the same at 91.327% when pulling 4b08f42 on martyan:master into 02faa3c on react-component:master.