bug grab bag for table

[berycz]

• columns__select__header__attrs__class = {"text-center": True} doesn't work for me for some reason 🤔 <th> wont get the class
  weird is, that columns__select__header__attrs__title = "Foo" works

• FIXED: 'Select all' not translated in style_*.py

• bs5 could have <i class="bi bi-check-square"></i>, so no need for Font Awesome

• FIXED: js_select_all.html isnt translated

• js_select_all.html could go into iommi.js, I'm just not sure, how to deal with js translates (django way, or custom window.iommi.translates)

FIXED: also I'd drop the IE11 support in js_select_all.html, useless piece of code :)