property-placeholder.xml

[Tom Zeller]

> I was wondering if there was any way to inject it programmatically like we
> do with some of the post processors now.

I had thought about injecting the placeholder configurer in contexts
created by SpringSupport.newContext(), but because we have custom
placeholder prefix and suffixes, I thought that we should expose that
bit of wiring in case a deployer needs to change it back to the
defaults for whatever reason.

I'm not opposing the suggestion, but because we changed the default
Spring behavior I thought that change should be explicit.