Support for trailing commas in Import/Export statements

[xjamundx]

Babel supports this, I need to check with the spec:

• import {y,} from 'x';
• export {y,} from 'x';

[sebmck]

It's in the spec.

15.2.2

NamedImports :
{ }
{ ImportsList }
{ ImportsList , }

15.2.3

ExportClause :
{ }
{ ExportsList }
{ ExportsList , }

[nzakas]

Thanks @sebmck, we will get this fixed.

[xjamundx]

Putting my parser hat back on and fixing this... 🎩

[xjamundx]

import case works. Need to add export. Will file in the morning!

[xjamundx]

Okay should be ready to go