Sync zoneinfo database with tzdata2011m from munnari.oz.au

Sync zoneinfo database with tzdata2011m from munnari.oz.au

asia:           8.68 -> 8.69
australasia:    8.27 -> 8.28
backward:       8.9  -> 8.10
europe:         8.38 -> 8.39
northamerica:   8.49 -> 8.50
southamerica:   8.50 -> 8.52
zone.tab:       8.49 -> 8.50

* asia, australasia, northamerica: Bump version for tzdata2011l.

* europe, backward: Pridnestrovian Moldavian Republic (Europe/Tiraspol)
    has followed much of Russia, and will retain "summer time" year round
    (that is no time transition is due Oct 30). This reintroduces a zone
    that had earlier been removed, and so removes the "backward" link.

    On the other hand, Ukraine have decided not to follow, so the change
    which had been made in preparation for that in tzdata2011k is now
    reverted, and there will be a transition on Oct 30.

* southamerica: The change to Bahia, Brazil, that introduced summer time
    (following the regular Brazil rules, so commencing this year on
    Oct 16 - last SUnday) that was mooted before tzdata2011l was released,
    but withdrawn because the change was not yet official, has now been
    ratified.