Default include_path

Hello Internals, I've recently discovered that the default include_path is dependent on whether pear is enabled. I don't remember the discussion but we have decided to deprecate pear. This has the implication that going forward there won't be a standard place for PHP code in the installation prefix. I think we should keep this include directory, separate it from pear, and always create it. It is sometimes useful today, and I think in the future it might be helpful to have it if we ever create "extensions" in PHP. Any objections?