Update README.md

Typo & bugfix
Order ancestors by lft to get logical sorting (in stead of random)

More sorting could be done in other methods. I have no time right now to patch. May be later :-)
Fix SQL error from empty parent_id when moving root nodes
Modify empty parent_id check to use "is_null" function. Merges pull-request #10."
Add initial test suite (still incomplete).
Merge branch 'patch-2' of git://github.com/dirkpostma/baum into dirkpostma-patch-2
Order children by lft column by default.
Add logical sorting order by default and some sibling tests.
Add tests for movement operations.
Merge branch 'patch-1' of git://github.com/dirkpostma/baum into dirkpostma-patch-1
Add tests for moving, moved events dispatch.
Add immediateDescendants/getImmediateDescendants query scope and getter.
Add left-out sorting option on  scope.
Update CHANGELOG