def canonize_path(aPath,aRootPath=nil)
			path = path_combine(aRootPath,aPath)
			path = real_path(path) if path
			path
		end
def canonize_path(aPath,aRootPath=nil)
			path = path_combine(aRootPath,aPath)
			path = real_path(path) if path
			path
		end
takes a path and combines it with a root path (which defaults to Dir.pwd) unless it is absolute
 the final result is then expanded