#13 path function names

[Mark Lentczner]

The function names for path managment in both Path and
NameSpace are lousy.

Currently:
NameSpace::path() -> given a Path return an
ObjectPointer
NameSpace::pathTo() -> given an ObjectPointer return a
Path

Path::appendPath() -> if the argument is a relative path,
treat the current path as the base and do the relative path
computation, if the argument is absolute, just set the path

These are hard to remember, poorly named, and perhaps
even poorly factored.