Enable encoding selection during file imports

[HardcoreMagazine]

Feature

As says in the title.
I suggest to add a drop-down list in the FILE IMPORT modal window.
This would allow international file support, as in not just default UTF-8 used by "file.text()" method.

Alternative solutions or implementations

Simplest implementation possible (encoding hardcoded):

1. HardcoreMagazine@17b037a
2. HardcoreMagazine@9894123

Other context