* Another big chunk of v4-require-isms
* Allow `#lang framework/keybinding-lang' for keybinding files
* Move hierlist sources into "mrlib/hierlist", leave stub behind
svn: r10689
in them, which caused problems with main-collects not identifying
paths as paths in the plt tree. The solution is to use expand-path
for these things, which normalizses multiple slashes to a single one.
While I'm at it, I did the same for dirs.ss, so it produces more
consistent paths for code that might want to rely on it.
(Also did some reformatting.)
svn: r4477
