Button not registered in FileUpload

[bgorhoball]

Hello,

I am using primevue 2.0.9 and have some questions on FileUpload -

1. Icon of item remove button
   The icon to remove the items on the RHS could not be rendered as shown below. It seems the Button component is not yet registered in the components
   

2. webkitdirectory support for the input tag
   As per the MDN web, is it possible to have 'webkitdirectory' added as a property just like 'multiple'?

I could create PR if needed. Thanks a lot!

[cagataycivici]

For directory support, please monitor;

#499