Added basename() to path

This will be useful for finding the file referred to by a path.

libsaria/path/__init__.py

@@ -7,6 +7,7 @@ exists   = os.path.exists
 is_dir   = os.path.isdir
 expand   = os.path.expanduser
 splitext = os.path.splitext
+basename = os.path.basename
 join     = os.path.join
 makedir  = os.mkdir
 rm       = os.remove