0.8.7.22:

0.8.7.22:
	RIP (physical) PATHNAME-VERSION significance
	... remove all internal discrimination based on the version
		field if the pathname involved has the Unix host.
	... parsing of a physical pathname namestring (i.e. again either
		explicitly or implicitly on the Unix host) never produces
		a version from the namestring.
	... make :if-exists :new-version behave like :if-exists :error,
		because despite weasel-words in CLHS someone might
		legitimately expect :if-exists :new-version not to
		clobber the old version.
	... (this latter needs to be revisited, when OPEN is made aware
		of logical pathnames and the wacky logic they impose; we
		can support :new-version with LPNs, but only if OPEN is
		clever).
	... make pathnames more likely to be read/print consistent, by
		throwing errors in more cases (we now pass PFD's test for
		that, not that it's that stringent).
	... throw errors on use of (:absolute :up) and friends in CL
		operators, but...
	... don't throw error on creation, and in fact test in sb-posix
		that we can use #p"/../" for what it means.