digraphs cannot be inputted in different order

[FelipeLema]

Describe the bug
Digraphs should be able to inputted in any order (as long as either key combination exists). They're note

To Reproduce

1. Open new file
2. Press i to change to insert mode.
3. Ctrl+k to start digraph input
4. Press '
5. Press o

Expected behavior
Should write ó like nvim does, but writes nothing (asumes it's wrong input).

Environment (please complete the following information):

• Extension (VsCodeVim) version: 1.1.0
• VSCode version: VSCodium 1.31.1
• OS: Windows

[jpoon]

cc @jbaiter

[jbaiter]

Thanks for reporting, I didn't know that this was possible in vim! Should be an easy fix, I'll see to it that I have a PR ready by this weekend.