We have a most confusing situation here, which is most of all pretty

We have a most confusing situation here, which is most of all pretty
weak for protecting us from making mistakes.
First there is a config_root (PORTAGE_CONFIGROOT) which can be a path
somewhere, from which all paths need to be relative (e.g.
etc/portage), hence those constants do NOT have EPREFIX, because
config_root contains EPREFIX by default -- overriding it loses the
EPREFIX as one would expect.
Second there is target_root (ROOT) which is to install somewhere
completely else, in Prefix of limited use.  Because this is an offset
always given, the EPREFIX should always be applied in it.  Those
constants (like VDB_PATH) DO have EPREFIX.

svn path=/main/branches/prefix/; revision=11082