Modifiers were moved into Key in 22169e22f, but the separate Modifier field
on types.Binding and gocui.keybinding was left behind. The keypress matcher
already compares modifiers via Key.Equals, so the old field is never read on
the dispatch path; it just got passed through SetKeybinding and stored.
Drop it from gocui.keybinding, types.Binding, and the SetKeybinding /
DeleteKeybinding signatures, and remove every now-redundant Modifier:
gocui.ModNone struct field. Mouse bindings keep their own Modifier (on
ViewMouseBinding) since that path still consults it.
I copied all files except dot files (.github and .gitignore), the _examples
folder, and go.mod/go.sum.
At some point we may want to copy the files back to the gocui repo when other
clients (e.g. lazydocker) want to use the newer versions of them.
Apparently this was an attempt at working around go's lack of default arguments,
but it's very unidiomatic and a bit confusing. Make it a normal parameter
instead, so all clients have to pass it explicitly.
We want to show an error when the user tries to invoke an action that expects only
a single item to be selected.
We're using the GetDisabledReason field to enforce this (as well as DisabledReason
on menu items).
I've created a ListControllerTrait to store some shared convenience functions for this.
