First Commit

Added Functionality of Parentify.

If a node is deleted, all descendants are added to the parent
of the deleted node.
added test cases
test improved to consistency
removed unwanted test
method and test case modified to be able to rootify the subtree,
 incase the deleted node is a root.

Updated the README.rdoc
README - Replaced TAB with Space
Revert "README - Replaced TAB with Space"

This reverts commit 1f52799883bc153ea5fe382ddbfb7b0347b2738a.
minor changes in the README
Added a before_save callback for cache_depth as well as the existing before_validation callback. This ensures that all descendants in a subtree have their depth cache updated when the subtree is moved.
Added short alias :root? to existing is_root? method
base_class replace ancestry_base_class
Updated README.
-- renamed the orphan strategy
Applied [82f6a33] Fixed it for Rails 3.2 and broke it for 2.x, changed version 1.2.6 and activerecord dependency to >= 3.0.0
Dropped support for primary_key_format
Added rake task test_all
Bumped version to 2.0.0
Bumped activerecord dependency to >= 3.0.0
Fixed tests for 3.0.0
Removed backwards compatibility workarounds
Replaced valid? in before_save callback with simpler sanity check
Minor refactors
Test to cover ticket: https://github.com/stefankroes/ancestry/issues/44#comment_1129700
always discard scope when looking up root & parent
Merge remote-tracking branch 'ridsagrawal/master'

Conflicts:
	lib/ancestry/instance_methods.rb
fix readme, small fix in restore_ancestry_integrity!