packaging: ship all help .txt files on WiX These are technically not needed. But it is easier to ship all files than to cherry-pick. A `make install` will copy these files, so the new behavior is consistent with that. This also makes WiX consistent with Inno, which is my main reason for doing this. If we don't want to ship the files (which is a valid argument), I think we can do that in a follow up. Differential Revision: https://phab.mercurial-scm.org/D7166