Changing license to be MIT/Apache

[andreypopp]

Now react-forms is licensed under MIT. We are going to change license to be MIT/Apache dual license. The reasons are simple — some of our clients prefer to work with Apache as it provides additional guarantees for them.

@maslianok @cusspvz @ifunk @davidkpiano you've contributed code to react-forms, are you ok with the license change? Are you willing to relicense your contributions under MIT/Apache?

[cusspvz]

@andreypopp I don't see a problem with that.

[ifunk]

@andreypopp Fine with me.