Moved convert_etree into tater.base.node.
REfactored tater Node to implement dict interface.
Eliminate bogus __nonzero__ invocation.
node.items is now node.tokens
Make node behave more like a dict
Fix deplorable Renderer hack for context managers
Move etree visitior
Added DictSetDefault ctx manager
Convert Node into a real dict
Generalize __eq__ to consider subclass attrs
Dicty objects should never by hashable
Node overhaul
little rename