Icon package support

[cirediew]

Please consider supporting rendering icon from packages.
At this moment you cannot use iconStyle with iconData with an icon package. For example https://pub.dev/packages/material_design_icons_flutter.

To change this please take a look at this https://stackoverflow.com/a/64930625/6704033

[JHBitencourt]

Hey @cirediew , thanks for the issue!

I'll try and experiment on that.
For now, consider looking at this answer: #14 (comment)