model: fix the VersionedDocument fields

After stopping using the metaclass to perform the hocus pocus for the
VersionedDocument the TopLevelDocumentMetaclass wasn't setting the field
names when creating the class. This commit peforms all the things that
the metaclass should be doing but isn't since it is abstract.
Merge pull request #2 from damoxc/fix-versioned-document-fields

model: fix the VersionedDocument fields
removed print statements
added test to check for inherited documents
check for compound key ids and fetch them as dict
add basic site structure models
added skeletal structure and tests for pages
fix to allow base class to inherit
fixed Url parent class
added skeleton url lookup
reverse delete is not supported on embeded fields
basic test cases for pages
added missing test global setup
updated main to be called without config
inherited from the wrong class
removed stock view
removed stock tests
explicitly state ref for future version of mongoengine
added bock and updated site
updated page view to correctly lookup site and url