[enh] use baron path to find a redbaron node
[enh] get the baron path of a redbaron node

The path is relative to the FST tree root node. You could say it is
absolute.
[mod] test baron path from and to redbaron node
[mod] better function name
[mod] better test for path emptiness
[mod] better variable naming
[mod] add Path class to handle path to node
[fix] declare class methods as class method
[mod] change api to give an alternate constructor for more explicit behavior
Merge branch 'master' into baron_path
[doc] document .path()
[fix] add missing inheritance from object to Path class
[mod] class docstring should be a the class level
[doc] include Path() docstring into doc
Merge pull request #12 from Psycojoker/baron_path

Add conversion between redbaron node and baron path