This may seem like a small change, but it's going to be used in a lot of different places (and it was a pain in the neck to do this because it didn't fit well into the normal serv_upgrade.c module). This will eliminate the places where a user name that has spaces or punctuation in it is no longer ambiguous. Now I don't have to worry about whether the software wants "ignatius_t_foo...@example.com" and whether the underscores are actually in the username or if they're converted from spaces or whatever.
Furthermore, these are now all the same: "IGnatius T Foobar" "ignatius t foobar" "ignatius.t.foobar" "ignatiustfoobar" "ig.natius-t_foo.BAR" Yes, there's a reason I'm doing this! It will make the user's identity token UNAMBIGUOUS in protocols like XMPP, where we have in the past had to deal with identities that cannot have spaces, but then we have to replace the spaces and we don't know for sure that they're actually spaces. So a user whose screen name is "The AWESOME D00D!!!1" will be indexed as "theawesomed00d1" in XMPP. No, I don't actually care much about XMPP these days, but this is going to make ActivityPub work a whole lot better when I implement that.
