started schema-constraints
added schema-constraints
Update cookbook.rst

A method name is incorrect in a comment.
some adjustments
some adjustments
Merge remote-tracking branch 'upstream/master' into schemaconstraints

Conflicts:
	py2neo/neo4j.py
Merge remote-tracking branch 'upstream/master' into schemaconstraints

Conflicts:
	py2neo/neo4j.py
Merge remote-tracking branch 'upstream/master' into schemaconstraints
doc theme update; fixes #283; fixes #284
fixes #281
renamed all `graph_db` to `graph`
fixes #282
removed support for Python 2.6; fixes #243
updated release notes
Merge pull request #278 from tftdias/patch-1

Update cookbook.rst
httpstream: Resource init
Merge pull request #277 from umeier/schemaconstraints

Schemaconstraints
Merge branch 'master' into spatial-extension