Merge branch 'master' of github.com:ITCase/sqlalchemy_mptt

Author: uralbash

README.md

@@ -2,7 +2,52 @@
 [![Coverage Status](https://coveralls.io/repos/ITCase/sqlalchemy_mptt/badge.png)](https://coveralls.io/r/ITCase/sqlalchemy_mptt)
 [![Stories in Ready](https://badge.waffle.io/itcase/sqlalchemy_mptt.png?label=ready&title=Ready)](https://waffle.io/itcase/sqlalchemy_mptt)
 
-soon...
+Library for implementing Modified Preorder Tree Traversal with your SQLAlchemy Models and working with trees of Model instances, like django-mptt.
 
-![ScreenShot](https://rawgithub.com/ITCase/sqlalchemy_mptt/master/docs/img/1_sqlalchemy_mptt_example.svg)
-![ScreenShot](https://rawgithub.com/ITCase/sqlalchemy_mptt/master/docs/img/2_sqlalchemy_mptt_traversal.svg)
+![Nested sets example](https://rawgithub.com/ITCase/sqlalchemy_mptt/master/docs/img/1_sqlalchemy_mptt_example.svg)
+
+The nested set model is a particular technique for representing nested sets (also known as trees or hierarchies) in relational databases.
+
+![Nested sets traversal](https://rawgithub.com/ITCase/sqlalchemy_mptt/master/docs/img/2_sqlalchemy_mptt_traversal.svg)
+
+Installing
+----------
+
+Install from github:
+
+    pip install git+http://github.com/ITCase/sqlalchemy_mptt.git
+    
+PyPi:
+
+    pip install sqlalchemy_mptt
+
+Source:
+
+    python setup.py install
+
+Usage
+-----
+
+Add mixin to model
+
+```python
+from sqlalchemy import Column, Integer, Boolean
+from sqlalchemy.ext.declarative import declarative_base
+
+from sqlalchemy_mptt.mixins import BaseNestedSets
+
+Base = declarative_base()
+
+
+class Tree(Base, BaseNestedSets):
+    __tablename__ = "tree"
+
+    id = Column(Integer, primary_key=True)
+    visible = Column(Boolean)
+
+    def __repr__(self):
+        return "<Node (%s)>" % self.id
+
+Tree.register_tree()
+```
+Now you can add, move and delete obj