A few more fixes related to AEST/AEDT etc.  (Thanks to Tim Parenti.)

* Theory: Use CST instead of EST in the example, so that it matches
the current database.
* antarctica (Antarctica/Casey): AWST, not WST.
* asia (Asia/Jayapura): ACST, not CST.
* australasia: Prepend "[A]" to "EST" in quote about EST.