Bundle Station Master v0.6.0: updates stop destroying games in progress

Pin moves to v0.6.0, package version to 0.6.0:0.

README and instructions.md both promised the opposite of what now happens
and had to be rewritten: an update keeps games in progress unless the rules
actually changed, and a game that genuinely cannot replay is named in the
log rather than described as a version mismatch.

Verified on phoenix.local by doing the thing the release is about. A game
(MAIL-4571) was created on the installed 0.5.6:0, then this build was
installed over it. All four saved games on the volume came back:

  Resuming 4 saved game(s)…
  Resumed HOPPER-4607  — 37 intents replayed.   (written under 0.5.2)
  Resumed TRESTLE-5109 —  5 intents replayed.   (written under 0.5.3)
  Resumed TENDER-8092  — 38 intents replayed.   (written under 0.5.5)
  Resumed MAIL-4571    —  0 intents replayed.   (written under 0.5.6)

The first three had been refused on every boot since the release that
stranded them. They were never damaged, only unreachable, and replaying
them is all it took to get them back — which is the clearest evidence that
the version comparison was answering the wrong question. All four now show
in Games in Progress with the correct Day, Stage and waiting-on player.

instructions.md

@@ -60,8 +60,7 @@ a game that will never be finished — otherwise it sits there, and comes back e
 service restarts. It cannot be undone, so the game's save is handed back to you when it happens:
 that text is the only copy left, so keep it if the game was worth watching.
 
-> One thing to know before you update this service: **games in progress do not survive an
-> update.** The rules can change between versions, so a half-played game recorded under the old
-> ones is refused rather than resumed under rules it was not played by. Nothing is deleted, and
-> going back to the previous version makes them playable again — but the safe habit is to finish
-> games before updating.
+> **Games in progress normally survive an update of this service.** When the update changes the
+> rules of the game itself, a half-played game cannot be resumed under rules it was not played by,
+> and that game is set aside rather than continued — you would see it disappear from the lobby.
+> Nothing is ever deleted, so going back to the previous version makes it playable again.