WARN of the non-use of optimizedAliasResolution

As we found in SLING-12025, disabling the optimizedAliasResolution changes the behavior of the mapping result. This can be clearly considered a bug, but as it is part of the ResourceResolver for quite some time (although not default), we cannot fix or remove it that easily.

We should write a WARN message into the log, when the optimizedAliasResolution is NOT used. The wording in the configuration (as shown in the OSGI Webconsole) should be adjusted too.

The removal of this code path should be considered as next step, taking place in 12+ months earliest.