s-tab support for TERM linux

I wrote an application I want to be as portable as possible. Found that s-tab didn't work in the linux console (TERM=linux). Found a great article talking about how linux doesn't match ANSI/VT for everything: https://unix.stackexchange.com/a/238932

I have provided a pull request that will simply add an additional escape sequence to prompt_toolkit.input.ansi_escape_sequences that works. (Rename to .py. Import. Call patch() within.)

Until a fix is incorporated and released, I'm using the attached file as a workaround, as I'd like to not have an application dependency on a non-released (ie, pypi) version of prompt-toolkit.

patch_for_linux.txt

Putting up this issue and not just submitting a pull request for a couple of reasons.

First, is the patch in my pull request the best way to implement this? Shouldn't break anything as far as I know, and seems to already be TERM=linux alternative sequences in there already.

Second, any value to having prompt-toolkit read TERM and build ANSI_SEQUENCES dynamically based on that?

Start with prompt_toolkit.input.ansi_escape_sequences and inspect the attached patch_for_linux.txt, paying attention to the existing TERM=linux alternatives. Determine whether the additional escape sequence is sufficient or whether TERM-specific sequence construction is needed. Done means s-tab works in the Linux console without breaking existing terminal input behavior.