Add PowerPC release notes for 3.5.
Add PowerPC release notes for 3.5.

Here's my take on 3.5 changes for PowerPC.  Others please feel free to add,
edit, delete as desired.

Thanks,
Bill

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@214403 91177308-0d34-0410-b5e6-96231b3b80d8

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