php-fig/fig-standards — pull request #214 by philsturgeon (2013-10-22 23:46:01+00:00)
Title: [PSR-4] Bye Bye Resource

This was done apparently because the original wording suggested remote file systems were not allowed. We now use phrases like "target file system" which I believe covers this use-case and requires no extra definition. Base Directories and Mapped File Paths are back people.