Create a file upload component

[JonatanSalas]

Add support for drag and drop file upload component

[andrerpena]

I'll come back to this as soon as this is complete: redux-autoform/redux-autoform#45

Having the features we have now working, tested and DOCUMENTED is far more important than adding new features.

[JonatanSalas]

100% agree with you @andrerpena! I will try to add test for components with enzyme.

[andrerpena]

+1, really.. Enzyme seems really great

[JonatanSalas]

@andrerpena the guys from airbnb are really good with js!